Qllje  i.  1.  Btll  ICtbrarg 


Nortit  (Earolina  ^tatp  ImnerHitg 

Q,K475 
B4 


S00366757 


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DEC  5    ^573 
OCT  2  1  1989 


JDN  3  0  2M5 


i  1 


TREE  ANCESTORS 


A  GLIMPSE  INTO  THE  PAST 


BY 
EDWARD  WILBER  BERRY 

Professor  of  Paleontology  in  the  Johns  Hopkins  University 


'  For  it  had  bene  an  ancient  tree, 
Sacred  with  many  a  mysteree." 

Shepheards  Calender:  Febniarie,  197,  19S 


BALTIMORE 

WILLIAMS  &  ^^'ILKINS  COMPANY 

1923 


■Si 


Copyright  1923 
WILLIAMS  &  WILKINS  COMPANY 

Made  in  United  States  of  America 

All  rights  reserved,  including  that  of  translation 

into  foreign  languages,  including  the 

Scandinavian 


COMPOSED  AND  l-RINTED  AT  THE 

"WAVERLY  PRESS 

By  The  Williams  &  Wilkins  CoiiPAXV 

Baltimore,  Maryland,  U.  S.  A. 


CONTENTS 

I.  Introduction 1 

II.  Geological  principles 3 

III.  Methods  of  preservation  of  fossil  plants 10 

IV.  Geological  time  and  methods  of  reckoning 14 

V.  The  later  geological  history  of  North  America 16 

VI.  The  present  forests  of  North  America 28 

VII.  The  sequoias  or  big  trees 39 

VIII.  The  bald  c}T)ress 56 

IX.  The  walnuts  and  hickories 68 

X.  The  willows  and  poplars 81 

XI.  Birch,  hazel,  hornbeam  and  alder 96 

XII.  The  beech 119 

XIII.  The  oak  and  chestnut 129 

XIV.  The  elm,  planer  and  hackberry 146 

XV.  The  platanus  or  buttonball 157 

XVI.  The  magnolia  and  tulip-tree 165 

XVII.  The  sweet  or  red  gum  and  witch  hazel 181 

XVIII.  Locust,  coffee-bean  and  red-bud 191 

XIX.  Sumach  and  holly 206 

XX.  The  maple 216 

XXI.  The  ash 225 

XXII.  The  linden  or  basswood 233 

XXIII.  Dogwood  and  gum 239 

XXIV.  Sassafras,  spice-bush  and  bay 247 

XV.  The  persimmon 255 


10890 


ILLUSTRATIONS 

The  giant  bald  cypress  of  Santa  Maria  del  Tule Frontispiece 

Fig.    1.  Map  showing  the  early  Upper  Cretaceous  geography  of  North 

America 18 

Fig.  2.  Map  showing  the  later  Cretaceous  history  of  North  America.  .  20 
Fig.    3.  Map  of  the  maximum  extent  of  Eocene  seas  in  North  America.  .     22 

Fig.    4.  Map  showing  Oligocene  conditions  in  North  America 24 

Fig.    5.  A  cone-bearing  twig  of  the  big  tree 40 

Fig.    6.  A  cone-bearing  twig  of  the  modern  redwood 44 

Fig.    7.  A  cone-bearing  twig  of  a  widespread  Cretaceous  big  tree 49 

Fig.    8.  A  cone-bearing  branch  of  a  common  Miocene  sequoia 50 

Fig.    9.  Map  of  the  world  showing  the  present  and  past  distribution  of  the 

sequoias  and  their  probable  paths  of  dispersal 54 

Fig.  10.  Map  of  the  world  showing  the  present  and  past  distribution  of  the 

bald  cypress 62 

Fig.  11.  Map  of  southeastern  North  America  showing  the  present  and 

Pleistocene  range  of  the  bald  cypress 66 

Fig.  12.  Map  of  the  world  showing  the  present  and  former  distribution  of 

the  hickories 70 

Fig.  13.  Map  of  the  world  showing  the  present  and  past  distribution  of  the 

walnuts 74 

Fig.  14.  ]\Iap  showing  the  present  and  past  distribution  of  the  other  mem- 
bers of  the  walnut  family 76 

Fig.  15.  The  winged  fruit  of  a  tropical  upland  member  of  the  walnut  family.     77 

Fig.  16.  Some  fossil  leaves  and  nuts  of  the  walnut 79 

Fig.  17.  Map  of  Europe  showing  the  limits  of  glaciation  and  the  Pleistocene 

occurrences  of  the  Arctic  willow 87 

Fig.  18.  Some  fossil  forms  of  willows  and  poplars 93 

Fig.  19.  Map  of  the  world  showing  the  range  of  the  modern  birches  and 

localities  where  fossil  forms  have  been  found 99 

Fig.  20.  Map  of  the  world  showing  the  existing  range  and  fossil  occur- 
rences of   the  hazel 104 

Fig.  21.  Map  of  the  world  showing  the  existing  range  and  fossil  occurrences 

of  the  hornbeam 108 

Fig.  22.  Map  of  the  world  showing  the  existing  range  and  fossil  occurrences 

of  the  ironwood HI 

Fig.  23.  ]\Iap  of  the  world  showing  the  existing  range  and  fossil  occurrences 

of  the  alder 113 


VI  TREE   ANCESTORS 

Fig.  24.  Some  fossil  birches 115 

Fig.  25.  Some  fossil  hazels 117 

Fig.  26.  Some  fossil  beeches 125 

Fig.  27.  Map  of  the  world  showing  the  present  distribution  of  the  oaks.  .  132 
Fig.  28.  Map  of  the  world  showing  the  distribution  of  the  beeches  and  of 

Castanopsis 135 

Fig.  29.  Map  of  the  world  showing  the  modern  distribution  and  the  fossil 

occurrences  of  the  chestnut 141 

Fig.  30.  IMap  of  the  world  showing  the  modern  distribution  of  Pasania  and 

the  ancestral  genus  Dryophyllum 142 

Fig.  31.  Some  existing  and  extinct  oak  leaves 145 

Fig.  32.  Some  existing  and  fossil  elms  and  hackberries 151 

Fig.  33.  Ancestral  forms  of  buttonball  leaves 161 

Fig.  34.  IMap  of  the  world  showing  the  fossil  occurrences  of  magnolias.  . .  166 
Fig.  35.  Map  of  the  world  showing  the  distribution  of  the  genera  of  the 

magnolia  family 166 

Fig.  36.  Map  of  the  world  showing  the  existing  distribution  and  fossil 

occurrences  of  the  tulip-tree 172 

Fig.  37.  Some  singular  atavistic  leaves  of  the  tulip-tree 175 

Fig.  38.  Some  fossil  leaves  of  the  ancestral  tulip-trees 177 

Fig.  39.  ]\Iap  of  the  world  showing  the  present  distribution  and  the  fossil 

occurrences  of  the  sweet  gum 183 

Fig.  40.  Some  fossil  leaves  and  fruits  of  the  sweet  gum 187 

Fig.  41.  Some  fossil  red  buds 192 

Fig.  42.  Some  fossil  locusts  and  coffee  beans 195 

Fig.  43.  Some  fossil  maple  leaves  and  fruits 219 

Fig.  44.  Map  of  the  world  showing  the  present  distribution  and  the  fossil 

occurrences  of  the  tupelo 245 

Fig.  45.  ]\lap  of  the  world  showing  the  present  distribution  and  the  fossil 

occurrences  of  the  sassafras 248 

Fig.  46.  Some  Pliocene  sassafras  leaves  from  Europe 250 

Fig.  47.  Map  of  the  world  showing  the  existing  and  geological  distribution 

of  the  persimmons 259 

Fig.  48.  Some  leaves  and  fruits  of  fossil  species  of  persimmon 261 


CHAPTER  I 

Introduction 

St.  Bernard  said:  ''Trees  and  rocks  will  teach  what  thou  canst 
not  hear  from  a  master,"  and  Tennyson  has  expressed  the  same 
thought,  of  the  mystery  and  romance  of  biology  wedded  to  geology, 
more  sonorously  in  the  following  lines: 

There  rolls  the  deep  where  grew  the  tree. 

O  earth  what  changes  hast  thou  seen ! 

There  where  the  long  street  roars,  hath  been 
The  stillness  of  the  central  sea. 

The  hills  are  shadows,  and  they  flow 

From  form  to  form  and  nothing  stands; 

They  melt  like  mists,  the  solid  lands. 
Like  clouds  they  shape  themselves  and  go. 

These  two  verses  compress  into  cinema-like  rapidity  what  went 
on  at  a  slow  rate  over  a  period  of  millions  of  years,  and  it  is  these 
glimpses  into  the  long  ago  that  stimulate  the  student  of  geology 
like  new  wine,  and  make  him  wonder  why  all  the  world  does  not 
forsake  the  trivial  affairs  of  life  and  spend  their  time  in  making 
bricks  for  the  temple  of  science  and  the  master  builder. 

The  sketches  which  follow  are  an  attempt  to  interest  the  general 
public  in  the  marvellous  history  of  some  of  our  trees.  Although  we, 
as  a  nation,  probably  because  of  our  seeming  limitless  natural 
resources,  have  been  somewhat  slow  in  awakening  to  the  necessity 
of  scientific  forestry,  there  has  always  been  a  large  pubHc  interested 
in  our  forest  trees,  as  witness  our  numerous  tree  books.  In  none 
of  the  latter,  however,  will  the  reader  get  any  idea  that  the  various 
tree  stocks  are  many  thousands  of  years  old,  or  that  their  abund- 
ance and  geographical  distribution  have  not  always  been  much  as 
we  find  them  today. 

The  selection  of  forms  in  the  following  pages  may  seem  arbitrary 
and  many  will  look  for  some  special  favorite  to  find  it  omitted, 

1 


2  TREE   ANCESTORS 

since  I  have  chosen  forms  whose  history  was  better  known,  but 
not  worn  threadbare,  and  omitted  others  where  the  evidence  was 
incomplete  or  conflicting,  as  in  the  case  of  the  pines,  spruce,  and 
their  allies. 

The  reader  need  know  no  geology  or  botany  as  all  unnecessary 
technicalities  have  been  avoided.  One  cannot,  however,  discuss 
history  without  some  sort  of  a  chronology,  and  I  have  therefore 
given  a  simplified  geological  time  table  in  Chapter  II  which  will  be 
sufficient  after  it  has  been  understood  to  render  clear  such  refer- 
ences as  appear  in  the  following  pages. 

The  main  theme  then  will  be  the  geological  or  distribution  in 
time,  and  the  geographical  or  distribution  in  space,  of  the  trees. 
Although  I  will  not  refrain  from  mentioning  the  usefulness  of  the 
trees  to  us  humans,  it  should  be  remembered  that  a  tree  is  no  longer 
a  tree  when  it  has  become  timber,  and  it  is  only  in  deference  to  a 
practical  people  and  to  a  forestry  which  regards  our  woodlands  as 
so  many  potential  board  feet  that  utihty  may  be  considered  as  a 
possible  avenue  to  a  more  general  appreciation  of  the  wonders  of 
their  present  state  and  the  grandeurs  of  their  past  history. 


CHAPTER  II 

Geological  Principles 

When  we  visit  the  Garden  of  the  Gods  and  learn  the  history  of 
the  beautiful  and  weird  shaped  masses  of  red  sandstone  to  which 
the  locality  owes  its  romantic  name — how  they  were  deposited 
originally  as  loose  sands  in  horizontal  beds,  were  subsequently 
solidified  and  bent  by  the  forces  that  built  the  Rocky  Mountains 
so  that  the  original  horizontal  bedding  became  perpendicular,  and 
were  subsequently  carved  to  their  present  proportions  from  solid 
sheets  of  rock  by  the  slow  action  of  rain,  wind  and  frost,  it  may 
readily  be  believed  that  strange  and  unknown  forces  of  great 
magnitude  were  operative  in  past  times.  The  same  feeling  is 
aroused  by  the  grandeur  of  the  Grand  Canon  of  the  Colorado  or 
by  the  columnar  lava  of  Fingalls  Cave  and  the  Giants  Causeway, 
or  even  by  the  majestic  lava  sheet  that  forms  the  Palisades  of  the 
Hudson.  And  if  we  have  ever  seen  the  overturned  folds  of  rock 
common  in  most  mountain  regions  or  especially  the  great  double 
fold  in  the  Glarner  Alps  south  of  Lake  Zurich,  we  may  feel  justi- 
fied in  concluding  that  very  different  and  titanic  physical  forces 
were  operative  on  the  earth  before  the  advent  of  man,  just  as  we 
know  gigantic  animals  flourished  in  past  geologic  times  and  just 
as  the  plants  alhed  to  our  modern  lowly  club  mosses  and  mares 
tails  were  tall  trees  during  the  coal  period. 

This  is  exactly  what  the  earlier  students  of  the  earth  thought. 
When  they  found  the  remains  of  marine  shells  in  the  rocks  of  the 
mountain  tops  they  concluded  that  vast  caverns  in  the  earth's 
crust  had  swallowed  the  waters  of  the  primeval  universal  ocean. 
When  knowledge  had  progressed  so  that  men  knew  that  the  traces 
of  former  life  in  each  succeeding  layer  of  rocks  differed  from  all 
others  both  earlier  and  later  they  concluded  that  mighty  cataclysms 
or  revolutions  of  nature  had  repeatedly  swept  the  life  ofif  of  the 
face  of  the  earth  and  that  each  time  this  had  happened  it  had  been 
subsequently  renewed  by  special  divine  creations. 

3 


4  TREE   ANCESTORS 

These  conclusions  were  all  rational  enough  in  their  day,  especially 
when  the  belief  was  well  nigh  universal  that  the  earth  was  only 
about  6000  years  old  as  estimated  from  the  bibhcal  chronicles. 
When,  however,  it  was  finally  reaHzed  that  nature  had  almost 
h'mitless  time  at  her  disposal  students  began  to  perceive  that  the 
apparently  insignificant  forces  which  we  still  find  at  work— the 
action  of  air  and  water  and  vulcanism,  and  the  slow  changes 
wrought  by  evolution,  were  the  agencies  that  had  accomplished 
such  tremendous  results  in  past  times. 

This  belief  in  the  uniformity  of  factors  and  the  interpretation  of 
the  past  in  terms  of  nature's  forces  that  we  find  acting  today  was 
christened  uniformitarianism  and  the  late  Sir  Charles  Lyell  (1797- 
1875)  may  be  regarded  as  the  high  priest  of  this  beHef.  It  is  quite 
possible  that  the  forces  of  nature  may  have  apparently  accomplished 
more  rapid  results  at  certain  times  in  the  history  of  the  earth  but 
it  is  very  doubtful  if,  during  the  time  when  the  ancestors  of  our 
forest  trees  have  flourished  physical  or  organic  history  moved  any 
faster  or  by  any  different  means  than  it  moves  today. 

This  is  one  of  the  great  principles  of  geology — that  we  may  legit- 
imately utilize  present  conditions  in  the  interpretation  of  the 
past,  or  in  what  Huxley  called  retrospective  prophecy.  We  may 
rest  assured  that  boreal  or  temperate  forests  did  not  flourish  in 
proximity  to  tropical  marine  waters,  and  that  insolation,  humidity, 
rainfall,  and  all  the  other  factors  of  environment  had  effects  on  the 
trees  of  past  ages  similar  to  their  effects  on  the  forests  of  today.  It 
is  as  unscientific  to  assume  that  trees  did  not  react  to  their  environ- 
ment during  the  Eocene  as  they  do  at  present  as  it  would  be  to 
assume  that  the  carrying  power  of  water  was  not  conditioned 
by  its  velocity  during  Eocene  time. 

A  second  principle  the  enunciation  of  which  will  be  helpful 
throughout  the  subsequent  discussions  relates  to  cHmate.  The 
human  race  since  its  reached  the  stage  of  written  traditions  has 
lived  under  chmatic  conditions  which  in  general  are  like  those  of 
the  present,  with  the  familiar  transition  from  torrid  through  tem- 
perate to  polar  chmates  in  passing  from  the  equator  to  the  poles. 
It  is  most  difficult  to  think  of  past  climates  as  in  any  way  different 


GEOLOGICAL   PRINCIPLES  i» 

from  those  that  we  have  known  since  childhood.  Hence  when  we 
hear  of  the  remains  of  bread  fruit  and  camphor-trees  in  latitude 
73°  north,  or  coal  seams  formed  by  the  accumulation  of  plant 
remains  in  both  the  Arctic  and  the  Antarctic  regions  it  might  seem 
as  though  the  poles  must  have  been  somewhere  else  at  the  time 
when  Greenland  was  the  land  of  verdure  that  its  name  would  seem 
to  indicate.  There  have  been  students  who  subscribed  to  the 
theory  of  wandering  poles  but  it  can  not  be  said  to  have  many 
adherents  at  the  present  time  and  physicists  assure  us  that  it  is 
imppssible.  The  truth  seems  to  be  that  geological  climates  in 
general  were  much  more  uniform  than  they  are  today — milder  in 
the  polar  regions  and  less  torrid  in  the  equatorial  regions.  This 
may  seem  to  be  an  exception  to  the  principle  of  uniformity  just 
enunciated,  but  this  is  only  apparent.  Through  a  combination 
of  causes  such  as  extension  and  elevation  of  the  land  surface  of 
the  earth  and  a  consequent  restriction  of  the  oceanic  areas,  and 
other  causes  not  yet  satisfactorily  formulated  there  have  been,  at 
widely  separated  intervals,  periods  of  glaciation  which  have  inter- 
rupted the  normal  more  uniform  climates  that  were  the  rule.  One 
has  been  recognized  in  the  pre-Paleozoic,  another  is  thought  to 
have  occurred  in  the  early  Paleozoic  but  this  may  be  confused  with 
the  earlier  one  just  mentioned.  A  third  was  ushered  in  many 
milHons  of  years  later  near  or  at  the  close  of  the  Paleozoic,  and  the 
fourth  and  most  widely  known  glaciation  is  the  one  which  after 
the  lapse  of  many  more  millions  of  years  immediately  preceded  the 
historic  period  and  witnessed  the  radiation  of  the  men  of  the  Old 
Stone  Age  in  Europe.  Men  of  this  Old  Stone  Age  were  witnesses 
of  the  great  Rhone  glacier  and  of  the  ice  sheet  that  covered  Britain, 
Scandinavia  and  the  north  German  plain. 

This  last  great  glacial  period  of  which  the  ice  cap  of  Greenland 
is  probably  a  surviving  remnant  continued  for  many  thousands  of 
years  and  was  marked  by  at  least  four  periods  of  prevalent  ice 
sheets  and  mountain  glaciers  and  by  intervening  interglacial  periods 
of  long  duration  during  which  the  climate  was  no  more  severe  than 
it  is  at  present.  These  were  much  longer  than  the  time  that  has 
elapsed  since  the  last  ice  sheet  dammed  the  valley  of  the  St.  Law- 


0  TREE    ANCESTORS 

rence,  and  many  students  believe  that  we  are  today  living  in  a 
fourth  interglacial  period.  This  would  account  for  the  present 
climate  with  which  man  is  familiar,  a  climate  anomalous  when 
compared  with  that  of  the  Tertiary  or  the  Cretaceous,  since  the 
glacial  periods  partially  due  to  the  extension  of  land  masses  and 
elevation  are  the  result  of  the  consequent  changes  in  the  atmos- 
pheric and  oceanic  circulation. 

Thus  a  second  principle  may  be  set  forth,  namely,  that  through- 
out the  bulk  of  geologic  time  climates  were  more  uniform  than  they 
are  at  present.  The  truth  of  this  statement  will  be  abundantly 
shown  when  the  former  distribution  of  our  forest  types  is  passed 
in  revdew,  although  the  actual  amount  of  change  has  usually  been 
overestimated. 

Geologists  in  dealing  with  the  rocks  of  the  earth's  crust  and  their 
succession  in  time  divide  them  into  geological  formations  which 
are  thus  the  units  of  geological  history  and  each  formation  may  be 
considered  as  a  page  .of  earth  history  or  a  phase  of  geological  time. 
From  the  remains  of  animals  and  plants  that  were  preserved  in 
the  rocks  of  a  geological  formation,  i.e.,  its  fossil  content,  and  from 
the  nature  of  the  enclosing  rock  that  constitutes  the  matrix  of  the 
fossils,  i.e.,  their  physical  and  mineralogical  character,  and  from  their 
relations  to  adjacent  rocks,  it  is  possible  to  in  a  measure  restore 
the  environment  which  existed  at  the  time  that  they  were  deposited, 
namely  the  topography,  temperature,  rainfall,  forestation,  etc. 

These  stratigraphic  units  or  formations  representing  phases  of 
time  are  grouped  together  in  larger  units  known  as  stages  (etages) 
representing  what  are  called  ages  of  time  and  these  in  turn  are 
grouped  into  units  of  still  larger  magnitude  known  as  epochs  of 
time  or  series  of  stages,  as  for  example  the  Eocene,  Oligocene  and 
Miocene  series  of  stages  or  epochs  of  time.  These  series  or  epochs 
are  further  grouped  into  systems  of  series  (rocks)  or  periods  of 
time,  as  for  example,  the  Carboniferous  system  or  coal  period,  the 
Cretaceous  system  or  chalk  period,  and  so  on.  The  Eocene,  Oli- 
gocene, Miocene  and  Pliocene  series  collectively  constitute  the  Ter- 
tiary period  during  which  both  the  Mammals  or  warm  blooded 
non-avian  am'mals  and  the  Angiosperms  or  flowering  plants  under- 


GEOLOGICAL  PRINCIPLES  7 

went  their  most  obvious  differentiation  and  distribution  over  the 
face  of  the  earth. 

These  systems  of  rocks  representing  the  history  of  periods  of 
time  are  themselves  gathered  together  into  groups  that  represent 
what  are  called  eras  of  time,  thus  the  Triassic,  Jurassic  and  Creta- 
ceous periods  constitute  the  Mesozoic  group  of  periods  or  the 
Mesozoic  era  of  time — the  era  of  gymnosperms  (more  familiarly 
conifers)  among  plants  and  the  era  of  reptiles  among  animals. 

All  this  may  seem  comphcated  and  abtruse  to  the  non-geological 
reader,  but  it  must  be  obvious  that  we  cannot  discuss  the  noble 
races  of  trees  that  have  passed  across  the  face  of  nature  in  past 
ages  without  a  definite  chronology  and  nomenclature,  any  more 
than  we  could  live  our  daily  lives  and  transact  its  affairs  comfort- 
ably and  effectively  without  time  pieces  and  calendars.  Nor  can 
we  compare  the  contents  of  the  rocks  of  different  countries  and  de- 
termine the  place  of  origin  or  the  subsequent  history  of  the  migra- 
tions and  extinctions  of  plants  or  animals  without  a  carefully 
worked  out  chronology.  Without  such  our  situation  might  be 
compared  to  that  in  civil  life  before  standard  time  was  adopted. 

The  following  somewhat  abbreviated  table  will  furnish  the  reader 
with  the  geological  divisions  that  it  will  be  necessary  to  use  in 
trying  to  picture  the  history  of  the  ancestors  of  our  trees.  It  also 
gives  a  few  of  the  facts  of  earth  history  and  organic  history  that 
will  serve  to  emphasize  and  fix  the  former  in  mind. 

To  those  who  notice  the  fate  of  the  leaves  each  autumn  it  may 
seem  that  for  any  adequate  geological  record  of  bygone  vegetation 
the  conditions  for  the  successful  preservation  or  fossilization  of 
parts  of  plants  must  have  been  very  different  in  the  past  from 
what  they  are  at  the  present  time.  Except  for  the  fact  that  the 
continental  masses  are  somewhat  larger  now  than  was  the  case 
for  the  greater  part  of  geological  time  this  is  not  so.  The  facilities 
for  fossilization  in  inland  and  upland  regions  have  always  been 
limited  to  lake  and  flood-plain  (river  overflow)  deposits.  Moun- 
tain lakes  have  frequently  preserved  marvellous  records  of  the 
contemporaneous  Kfe  as  that  of  the  Miocene  lake  of  Florissant  in  the 
heart  of  the  Colorado  Rockies  or  the  even  more  celebrated  Miocene 


TREE    ANCESTORS 


Quaternary 
period 

Pleistocene 
epoch 

Time  of  the  Ice  age  and  the  ancestors 
of  man.     Extinction  of  many  large 
animals  and  trees.     Evolution  of 
herbs.    Elevation    and    extension 
of  the  continents. 

CENOZOIC  ERA 

Tertiary 
period 

Pliocene 
epoch 

Cosmopolitan  forest  types. 
Elevation  of  the  Andes. 

Mammals  and 

Flowering 

plants 

Miocene 
epoch 

Zenith  of  development  of  forests. 
Elevation  of  the  Swiss  Alps. 

Oligocene 
epoch 

Culmination  of  Eocene  types.  Warm 

climate  with  some  aridity. 
Elevation  of  the  Pyrenees. 

Eocene 
epoch 

Forests  in  the  polar  regions. 
Beginning  of  elevation  of  Cordilleras. 
Community  of  Holarctica. 

Cretaceous 
period 

Earliest  known  palms.     Beginnings  of  the  modern 
forests  flora  mixed  with  survivals  from  the  fern, 
cycad  and  conifer  flora  of  the  older  Mesozoic, 

MESOZOIC  ERA 

Reptiles,  Cycads 
and  conifers 

Jurassic 
period 

Widespread  warm  seas,  marine  faunas  and  terres- 
trial floras. 
Origin  of  the  dicotyledons. 
Beginning  of  the  Sierra  Nevadas. 

Triassic 
period 

Shallow  seas  and  lagoons.     Widespread  red  con- 
tinental deposits.     Igneous  activity  and  moun- 
tain making. 

Land  extension. 

Appalachian  revolution. 

PALEOZOIC 
ERA 

Fishes,  ferns 
Giant  club  n 
Origin  of  the 
Old  folded  m 

since  worn 
Radiation  of 

and  amphi 

and  fern-like  plants, 
losses  and  horse  tail  rushes. 

seed  plants. 

ountain  systems  of  the  world  such  as  the  Caledonian, 
flat. 

invertebrate  phylae,  origin  and  evolution  of  fishes 
bians. 

lake  of  Oeningen  in  Baden  near  the  present  Lake  Constance.  In 
both  of  these  fossil  lakes  thousands  of  delicate  insects  and  the 
floral  and  foHar  organs  of  plants,  as  well  as  other  forms  of  Hfe  were 


GEOLOGICAL   PRINCIPLES  9 

preserved  in  great  variety  and  perfection.  Great  numbers  of 
plants  were  preserved  in  the  continental  deposits  of  our  own  wes- 
tern Tertiaries  and  amber  or  other  exudations  of  the  gum  of  trees 
has  frequently  hermetically  sealed  a  variety  of  delicate  and  other- 
wise unknown  fossils. 

Any  one  who  has  noticed  the  amount  of  variety  of  leaves  in  the 
bayous  and  estuaries  of  our  coastal  plain,  particularly  after  a  wind 
storm,  or  the  quantities  that  are  buried  by  fine  mud  in  the  spring 
freshets  of  the  rivers  have  little  difficulty  in  picturing  conditions 
favorable  for  fossilization  in  past  times.  When  it  is  further  realized 
that  the  geological  record  accumulated  not  through  a  few  but 
through  thousands  of  years  it  is  seen  that  this  record  is  no't  nearly 
as  inadequate  as  it  seemed  at  first  thought. 


CHAPTER  III 

Methods  of  Preservation  of  Fossil  Plants 

The  seasons,  whether  cold  and  warm  or  wet  and  dry,  succeed 
one  another  in  a  never  ending  series  ages  long.  Trees  ripen  their 
fruits  and  seeds  and  shed  their  leaves,  some  rapidly  and  some  slowly. 
Winds  contribute  windfalls  or  branches  to  the  forest  Utter.  These 
and  allied  processes  have  been  happening  since  plants  first  came  up 
out  of  the  primitive  oceans  and  covered  the  dry  land. 

In  regions  remote  from  water — -either  rivers,  lakes  or  ocean — there 
is  but  slight  chance  that  this  forest  litter  will  be  preserved.  It  is 
attacked  by  hosts  of  insects,  and  lower  plants  ranging  from  bacteria 
to  fungi,  and  the  greater  portion  is  finally  partially  or  wholly  oxi- 
dized. Swamps  may  preserve  logs  as  lignite,  or  scraps  of  vegeta- 
tion such  as  the  more  resistant  seeds,  or  cuticles  and  pollen  grains, 
but  the  great  bulk  of  the  swamp  accumulations  become  more  or 
less  amorphous  carbonaceous  masses  such  as  those  from  which 
coal  beds  have  been  formed. 

Fruits  and  seeds  are  designed  for  the  perpetuation  of  the  species, 
but  mortality  among  seeds  is  on  a  vast  scale.  They  have  to  fall 
or  be  carried  to  a  suitable  situation  in  order  to  sprout.  All  tlie 
non-carnivorous  higher  animals  levy  upon  the  products  of  the 
forest.  It  may  be  bears  coming  down  into  the  swamps  in  the  fall 
for  the  gum  berries  (Nyssa),  the  ever  present  squirrels  and  their 
allies  busy  with  the  oaks,  walnuts  and  hickories,  swine  devouring 
the  beech  and  oak  mast,  or  it  may  be  birds  or  fruit  bats  according 
to  species  and  clime.  While  man  has  been  on  the  scene  for  but 
a  relatively  short  time  he  has  probably  wrought  more  damage  than 
any  other  agency.  Consequently  it  might  seem  that  but  few 
relics  of  the  present  forests  are  being  fossilized  or  that  we  can  never 
accumulate  much  evidence  regarding  the  bygone  forests  that  clothed 
the  earth. 

While  in  a  general  way  deserts,  prairies,  open  savannas  and  pam- 
pas have  always  been  present  in  certain  areas  it  remains  true 

10 


METHODS   OF  PRESERVATION  11 

that  in  a  geological  sense  they  were  for  the  most  part  short  lived 
features  and  that  the  bulk  of  the  earth's  surface  has  been  for- 
ested until  modern  times .  . 

The  agents  of  fossilization  have  been  and  are  streams,  lakes, 
lagoons  and  seas.  A  constant  shower  of  life  falls  on  the  bosom  of 
the  waters.  Trees  have  their  roots  undermined  by  erosion  and 
topple  bodily  into  the  streams;  leaves,  fruits  and  sticks  make  up  a 
large  percentage  of  the  river  drift.  This  river  drift  may  travel 
near  or  far,  much  of  it  rots  beyond  recognition,  but  always  some- 
thing is  saved.  Logs  and  branches  are  stranded  and  buried  in 
river  bars  where  some  become  petrified.  Leaves  and  fruits  become 
water  logged  and  sink  in  slack  waters  where  they  are  covered  with 
mud,  or  the  forest  htter  on  bottom  lands  may  be  spread  with  a 
mantle  of  alluvial  mud  during  periods  of  high  water  and  thus  be 
preserved.  Anyone  who  has  seen  the  variety  of  leaves  and  fruits 
that  streams  are  constantly  carrying  in  our  own  country  or  the 
vast  amount  of  vegetable  drift  in  such  estuaries  as  the  Guayaquil, 
the  Amazon  or  the  Orinoco  cannot  doubt  that  the  present  is  pre- 
serving its  records  for  the  future  or  that  the  past  similarly  has  not 
failed  us.  The  forests  near  the  coast  contribute  like  things  to  the 
bayous,  estuaries  and  lagoons  or  carry  a  part  out  to  sea,  and  the 
same  processes  are  taking  place  around  all  the  innumerable  lakes 
and  ponds. 

The  actual  methods  of  preservation  are  divided  into  two  cate- 
gories— one  termed  infiltration  and  the  second  known  as  inclusion. 
In  the  first  the  plant  tissue  of  whatever  sort  from  trunk  to  seed  is 
more  or  less  completely  permeated  or  replaced  molecule  by  mole- 
cule by  silicic  acid,  calcium  carbonate  or  other  mineral  substances 
such  as  magnesium,  pyrite,  marcasite,  limonite,  etc.  According 
to  the  completeness  of  this  replacement  the  internal  structure  is 
preserved  with  more  or  less  fidelity,  often  to  such  an  extraordinary 
degree  that  the  histology  is  completely  decipherable,  and  such 
delicate  objects  as  the  mycelial  threads  and  spores  of  parasitic 
fungi  or  even  bacteria  are  recognizable.  Remains  preserved  as 
petrifactions  are  relatively  uncommon  although  characteristic  of 
regions  of  thermal  activity  like  the  Yellowstone  Park.     Calcified 


12  TREE    ANCESTORS 

plant  tissues  characterize  certain  horizons  in  the  coal  measures 
especially  in  England,  WestphaUa  and  Moravia.  Silicified  plant 
tissues  have  rendered  the  Permian  of  St.  Etienne  and  Autun  in 
France  famous,  and  quantities  of  Mesozoic  cycads  have  been  simi- 
larly silicified  especially  around  the  rim  of  the  Black  Hills.  Fossil 
woods  are  commonly  silicified,  opalized  or  jasperized  at  very  many 
localities  and  geological  horizons,  as  in  the  Arizona  National 
Park,  where  they  are  of  Permian  or  Triassic  age,  or  in  the  Yellow- 
stone Park  where  they  are  Tertiary  in  age.  Scattered  trunks  and 
fragments  of  petrified  wood  are  abundant  in  all  sandy  formations. 

The  second  general  method  of  preservation,  by  far  the  most 
common  mode  of  occurrence  of  fossil  plants,  is  by  simple  inclusion 
in  clay,  shale,  amber  or  other  material,  and  is  often  known  as 
incrustation.  The  bulk  of  the  fossil  plants  with  which  the  general 
public  is  familiar  are  of  this  type  of  preservation  which  often 
furnishes  the  most  beautiful  impressions  of  foliage  qr  even  flowers 
— the  finer  grained  the  sediment  in  which  the  plant  remains  were 
entombed  the  more  perfect  the  impression.  Thus  a  flocculent 
calcareous  mud  or  lithographic  stone  will  preserve  every  detail 
of  form,  or  a  fine  mud  like  that  of  the  fire  clays  beneath  coal  beds  or 
the  roofing  shales  above  them  will  be  crowded  with  the  delicate 
remains  of  the  plants  that  formed  the  coal,  or  a  fine  volcanic  dust 
falling  in  a  lake  will  preserve  most  beautiful  specimens.  Traver- 
tines will  encrust  the  vegetable  debris  of  deep  ravines  in  a  limestone 
country  as  in  the  case  of  the  celebrated  early  Eocene  travertines  of 
Sezanne  in  France,  or  the  younger  travertines  of  northern  Italy, 
or  stalagmite  will  preserve  the  litter  of  burrows  or  dens  of  animals 
or  of  men  of  the  Old  Stone  Age  that  lived  in  rockshelters. 

Plant  remains  preserved  by  inclusion  or  incrustation  may  have 
some  of  their  substance  preserved  as  carbon,  it  may  be  replaced 
by  salts  of  iron  or  other  mineral,  or  it  may  be  entirely  dissipated 
lea\'ing  only  the  impression  or  cavity.  Lignite  beds  and  coal  seams, 
or  the  impure  peats  of  buried  swamps  so  common  in  our  Pleisto- 
cene deposits,  are  examples  of  inclusion  (incrustation)  of  plants 
en  masse.  Occasionally  such  swamp  deposits  of  great  age  like 
those  of  Brandon,  Vermont,  or  of  the  Gennan  lignites,  both  of 


METHODS   OF   PRESERVATION  13 

Tertiary  age,  will  furnish  quantities  of  the  fruits  and  seeds  of  by- 
gone forests  that  flourished  on  their  sites.  Peat  bogs  are  veritable 
mines  of  more  recent  vegetable  history  and  where  their  contents 
are  studied  intensively  as  in  some  of  the  European  countries  they 
record  the  changes  from  sphagnum  to  rushes  and  the  succession 
of  willow,  birch,  pine  and  hazel  much  more  certainly  decipherable 
than  the  early  written  records  of  human  history.  Amber  and 
other  gums  frequently  contain  small  plant  fragments  in  an  exquisite 
state  of  preservation  but  the  great  bulk  of  fossil  foliage  was  buried 
in  shallow  water  muds  of  flood  plains,  lakes,  bayous  and  estuaries 
and  lagoons.  Occasionally  lignified  wood  may  retain  its  internal 
structure  and  by  special  methods  of  treatment  it  may  be  sectioned 
and  studied  microscopically. 

The  details  of  the  past  history  of  our  forest  trees  will  doubtless 
always  remain  imperfectly  known  but  this  knowledge  is  increasing 
rapidly  and  we  can  already  sketch  the  broader  outlines  of  the  his- 
tory of  a  large  number  of  our  trees  as  the  present  sketches  bear 
witness,  and  we  can  leave  to  the  future  the  filling  in  of  the  details 
of  these  pictures  when  we  know  that  these  broader  outlines  are 
not  founded  upon  fancies  or  theory,  but  upon  facts. 


CHAPTER   IV 

Geological  Time  and  Methods  of  Reckoning 

There  are  a  great  many  ways  of  estimating  the  duration  of  geo- 
logical time  or  the  age  of  the  earth.  This  is  a  fascinating  subject 
that  has  always  invited  speculation  by  physicists  and  biologists 
as  well  as  geologists.  Most  of  these  methods  are  dependent  on 
the  data  furnished  by  the  comparison  of  past  processes  with  present 
processes,  such  as  the  rate  of  the  formation  of  peat  in  bogs,  or  of 
stalactites  in  caverns,  or  the  rates  of  accumulation  of  different 
kinds  of  sedimentary  materials.  Other  methods  take  as  their 
basis  the  rate  of  cooHng  of  lavas,  the  amount  of  salts  in  solution 
in  the  oceans  compared  with  the  rate  at  which  rivers  are  bringing 
them  down  to  the  seas,  the  effects  of  tidal  stresses  in  retarding  the 
earth's  rotation,  the  rate  at  which  the  sun  is  supposed  to  be  losing 
its  heat,  and  by  other  less  obvious  methods,  such  as  the  state  and 
rate  of  change  of  radium  minerals  in  rocks. 

These  various  estimates  vary  through  very  wide  limits  since 
no  method  has  been  discovered  that  does  not  involve  a  variety  of 
unknown  factors.  There  is,  however,  a  certain  amount  of  con- 
cordance in  them  all  and  it  is  possible  by  carefully  estimating  the 
total  thickness  of  the  sedimentary  rocks  and  comparing  the  rate 
of  accumulation  at  the  present  time  of  the  different  kinds  of  rocks 
such  as  limestones,  sands  and  clays  to  get  a  rough  approximation 
of  the  time  necessary  to  account  for  the  deposition  of  similar 
materials  in  past  times.  That  the  results  are  not  accurate  is 
obvious  when  it  is  recalled  that  conditions  of  erosion,  amount  of 
material  and  all  of  the  other  factors  of  the  environment  vary  greatly 
so  that  one  limestone  may  accumulate  rapidly  and  another  slowly. 
Furthermore  very  Httle  account  can  be  taken  of  the  time  that  is 
represented  by  the  numerous  intervals  in  geological  history  when 
the  rocks  were  being  worn  away  by  erosion  and  the  resulting  de- 
posits are  beyond  our  ken,  or  when  the  surface  of  the  land  was  so 

14 


GEOLOGICAX   TIME  15 

nearly  flat  that  but  little  sediment  was  being  carried  into  the  seas 
and  lakes  and  being  deposited. 

It  is  obvjous,  however  that  this  method  while  very  inexact  is, 
when  carefully  done,  much  better  than  no  estimates,  and  when 
the  results  are  expressed  in  ratios  rather  than  in  actual  durations 
of  so  many  years  and  we  say  that  one  geological  period  was  twice 
as  long  as  another,  or  that  the  time  that  has  elapsed  since  the  last 
glacial  period  is  but  one  twenty-fifth  of  the  duration  of  the  whole 
Pleistocene,  we  are  naming  results  which  while  gross  from  the  view- 
point of  a  mathematician,  physicist  or  chemist,  are  very  satisfac- 
tory for  the  coarse  scale  of  geological  work. 

Geologists  have  grouped  the  rocks  of  the  earth's  crust  into  the 
following  five  major  divisions,  of  which  the  two  earlier  are  omitted 
in  the  table  given  on  a  preceding  page.  These  five  divisions  are 
in  the  order  of  their  age:  Archeozoic,  Proterozoic,  Paleozoic, 
Mesozoic,  and  Cenozoic.  The  stratified  rocks  that  contain  any 
abundant  display  of  the  life  of  their  time  are  embraced  in  the 
Paleozoic  (rocks  with  ancient  life),  Mesozoic  (rocks  with  middle 
life),  and  Cenozoic  (rocks  with  modern  life).  If  5  be  taken  to 
represent  the  duration  of  the  Cenozoic,  then  the  Mesozoic  will  be 
represented  by  12  and  the  Paleozoic  by  27.  Unity  is  commonly 
considered  as  a  million  years  but  it  may  be  more — it  certainly  is  not 
much  less. 


CHAPTER  V 

The  Later  Geological  History  of  North  America 

The  present  flora  of  North  America,  while  it  probably  antedates 
the  arrival  of  man  upon  this  continent,  has  not  remained  unchanged 
for  many  thousands  of  years  but  has  been  constantly  changing 
and  was  preceded  by  other  and  ancestral  floras  in  which  the  group- 
ing of  genera,  the  abundance  of  specific  types  within  these  genera, 
and  the  range  of  the  latter,  was  markedly  different  from  what  it 
is  today.  Glimpses  into  these  floras  of  the  past,  extending  back 
several  millions  of  years,  are  obtained  by  piecing  together  the 
evidence  furnished  by  the  fossil  remains  of  leaves,  fruits  and  stems 
preserved  in  the  rocks  of  the  various  geological  formations. 

The  majority  of  our  present  forest  types,  those  belonging  to 
the  class  Dicotyledonae  of  the  Angiosperm  phylum  (i.e.,  flowering 
plants  with  closed  seed  vessels)  have  an  ancestry  extending  well  back 
into  the  later  Mesozoic  or  Secondary  age,  as  the  old  geologists  called 
it.  The  conifers  (pines,  spruces,  hemlocks,  etc.)  while  less  numer- 
ous in  existing  genera  and  species  than  the  hardwood  deciduous 
trees,  making  up  for  it  in  a  measure  by  their  individual  abundance, 
are  of  enormous  antiquity,  representatives  of  this  group  being 
present  in  the  rocks  of  the  most  ancient  deposits  in  which  land 
plants  have  been  found. 

The  Mesozoic  age,  mentioned  above,  was  probably  the  scene  of 
origin  of  the  Angiosperms,  which  became  abundant  before  its 
close.  It  is  often  referred  to  as  the  age  of  conifers  (more  properly 
gymnosperms)  because  of  the  abundance  and  variety  of  coniferous 
types  at  that  time.  Faunally  it  is  known  as  the  age  of  reptiles 
among  vertebrates  and  the  age  of  ammonites  among  invertebrates. 
The  diagram  shown  on  page  8  serves  to  graphically  portray  the 
various  divisions  into  which  geological  time  has  been  divided.  In 
this  diagram  I  have  given  the  sub-divisions  of  the  geological  periods 
for  the  later  ones  only  as  those  are  the  ones  with  which  we  are 
especially  concerned  in  discussing  the  ancestors  of  our  forest  trees. 

16 


LATER   GEOLOGICAL  HISTORY   OF   NORTH    AMERICA  17 

Continental  outlines  have  changed  greatly  during  the  vast  lapse 
of  geologic  time,  but  the  student  of  modern  floras  need  not  concern 
himself  with  the  earlier  and  more  profound  changes  due  to  the 
past  movements  of  the  strand.  Those  changes  in  geography, 
topography  and  climate  which  have  gone  hand  in  hand  with  the 
development  of  the  present  flora  of  North  America  may  be  sketched 
in  a  few  words  and  need  not  be  carried  back  farther  than  the  Mid- 
Cretaceous. 

The  Mid-Cretaceous  shows  in  the  character  and  distribution  of 
its  rocks  that  the  continental  outline  of  North  America  had  assumed 
much  its  modern  form  except  for  the  extension  of  the  Gulf  of  Mexico 
over  Texas  and  into  Colorado  and  Kansas  as  is  indicated  upon  the 
accompanying  sketch  map  (fig.  1).  The  waters  of  the  Pacific  had 
submerged  a  narrow  strip  along  the  western  coast  and  the  Coast 
Range  was  not  yet  elevated.  In  marked  contrast  with  modern 
conditions  the  present  Rocky  Mountain  region  was  then  one  of 
low  relief  upon  which  were  being  deposited  scattered  fluviatile, 
lacustrine,  swamp  and  terrestrial  sediments. 

As  time  passed  both  the  Atlantic  and  more  of  the  Pacific  con- 
tinental borders  became  submerged  and  the  waters  of  the  Gulf  of 
Mexico  passed  northward  over  the  present  sites  of  the  Great  Plains 
and  Rocky  Mountains  to  become  mingled  with  the  waters  of  the 
Arctic  Ocean  which  had  advanced  up  the  valley  of  the  Mackenzie- 
River,  thus  forming  a  vast  but  extremely  shallow  Mediterranean 
Sea  and  widely  separating  northeastern  North  America  from  the 
Pacific  coast  strip  which  was  connected  directly  with  Siberia  across 
what  is  now  Bering  Sea.  This  stage  in  the  history  of  North  America 
is  shown  in  the  sketch  map,  figure  2.  ^ 

'  The  whole  continent  at  that  time  was  low  and  heavily  wooded, ' 
i  and  enjoyed  an  abundant  rainfall  throughout  and  a  climate  that 
was  much  more  uniform  than  it  is  at  the  present  time.  There  seems 
to  have  been  a  total  absence  of  frost,  and  palms  and  figs  were  able 
to  flourish  far  to  the  northward  of  the  present  international  bound- 
ary. Naturally  this  flora  was  very  different  from  that  of  today  as 
it  contained  many  elements  which  are  now  extinct  as  well  as  others 
which  are  no  longer  American,  and  a  curious  mixture  of  types 


TREE   ANCESTORS 


Fig.  1.  M.\p  Showing  the  Extent  to  Which  the  Sea  Encroached  on 
North  America  in  the  Early  Upper  Cretaceous 


LATER   GEOLOGICAL  HISTORY   OF   NORTH   AMERICA  19 

which  subsequently  became  climatically  segregated  as  the  climates 
became  less  uniform. 

At  the  time  of  which  we  are  writing  the  sheep-berry  and  camphor 
tree,  the  willow  and  alligator  pear,  the  oak  and  Sterculia  (a  tropical 
genus),  the  tulip- tree  and  the  fig,  the  walnut  and  the  palm,  and 
many  other  types  which  we  now  regard  as  essentially  tropical  on 
the  one  hand  or  temperate  on  the  other,  flourished  side  by  side. 
A  somewhat  analogous  grouping  of  temperate  and  tropical  forms 
occurs  in  certain  modern  forest  such  as  those  of  southern  Japan, 
New  Zealand,  southern  Chile,  etc.,  where  warmer  temperate  areas 
by  reason  of  the  water  vapor  in  the  air  and  the  heavy  rainfall, 
have  a  more  uniform  climate  than  is  normal  to  their  latitude  and 
support  a  vegetation  of  mixed  types  much  like  that  of  Upper 
Cretaceous  times. 

Some  of  the  forms  of  the  Rocky  Mountain  area  Cretaceous  flora 
such  as  the  magnolia,  sassafras,  fig,  persimmon  and  tulip-tree  still 
flourish  in  other  parts  of  the  American  continent,  while  others  such 
as  Araucaria,  Dammara,  and  various  Proteaceae  and  Myrtaceae 
once  abundant  throughout  the  Northern  Hemisphere,  became,  with 
the  lapse  of  time,  gradually  extinct  except  in  certain  isolated  areas 
in  the  Southern  Hemisphere.  Many  of  these  Cretaceous  genera 
were  more  diversified  than  they  are  in  the  modern  flora.  Thus 
there  were  over  ten  species  each  of  magnoKa,  sassafras  and  tulip- 
tree  in  this  region  at  that  time.  Sequoia  was  also  an  abundant 
element  throughout  the  Cretaceous  and  the  greater  part  of  the 
Tertiary  period.  Cretaceous  fan  palms,  sometimes  beautifuUy 
preserved,  have  been  found  in  Wyoming,  Colorado,  Vancouver, 
New  Jersey,  Maryland,  and  elsewhere. 

The  fortunate  discovery  of  extensive  beds  of  fossil  plants  of  this 
age  along  the  west  coast  of  Greenland  in  latitude  71°  shows  that 
much  the  same  assemblage  of  plants  grew  in  the  far  North  at  that 
time  as  are  found  in  beds  of  this  age  along  our  Atlantic  coast 
from  Martha's  Vineyard  to  Texas,  and  there  are  many  additional 
facts  pointing  to  the  conclusion  that  there  were  no  chmatic  or 
marine  barriers  between  northeastern  North  America  and  Europe 
nor  between  northwestern  North  America  and  Asia.     This  leaves 


20 


TREE    ANCESTORS 


Fig.  2.  Map  Showixg  tiie  Maxijium  Extent  of  Upper  Cretaceous  Seas  on 
TiiE  North  American  Continent 


LATER   GEOLOGICAL  HISTORY   OF   NORTH    AMERICA  21 

US  the  choice  of  two  areas  as  the  place  of  origin  of  the  flowering 
plants.     These  are  the  Arctic  region,  or  the  vast  and  geologically^ 
unknown  Asiatic  region. 

As  Upper  Cretaceous  times  drew  toward  their  close  the  conti- 
nental seas  became  more  restricted  and  the  shores  withdrew  from 
positions  indicated  by  the  solid  lines  indicated  on  the  accompany- 
ing map  (fig.  2).  At  this  time  the  Rocky  Mountain  region  within 
the  lined  area  on  the  map  became  a  region  of  delta  and  coastal  swamp 
deposits,  Vv^hich,  as  the  shallow  seas  silted  up  or  were  drained, 
extended  eastward  until  the  whole  of  the  present  plains  region  was 
one  of  scattered  swamps.  This  is  why  we  now  find  the  widespread 
and  valuable  lignitic  coals  throughout  this  area.  These  events 
brought  to  a  close  the  last  of  the  many  marine  submergences  of 
the  interior  of  North  America.  Henceforward  the  subsequent 
marine  invasions  of  North  America  were  strictly  marginal  and  of 
relatively  small  and  progressively  decreasing  extent. 

With  the  geological  changes  which  marked  the  close  of  the 
Cretaceous  in  North  America  and  with  the  gradual  elevation  of  the 
Rocky  Mountains  during  the  Tertiary  a  very  different  flora  came 
to  occupy  the  site  of  the  old  lowland  warm  temperate  forest.  This 
flora  during  the  early  Eocene  was  largely  temperate  in  its  character 
and  appears  to  have  invaded  western  North  America  from  the 
north.  Figs,  magnohas  and  palms  were  still  present  in  that  region 
but  in  dwindhng  proportions  and  the  forests  contained  very  many 
species  of  cottonwood,  sycamore,  hazel,  sheep-berry,  etc.  The 
coniferous  trees  Glyptostrobus,  sequoia  and  the  bald  cypress 
(Taxodium)  were  present  in  abundance,  and  a  curious  feature  was  _ 
the  presence  of  Ginkgo  of  which  only  a  single  Asiatic  species  sur- 
vives in  the  modern  flora. 

Southeastern  North  America  had,  at  this  time,  a  much  enlarged 
Gulf  of  Mexico  as  shown  on  the  accompanying  sketch  map  of  the 
Eocene  geography  (fig.  3).  The  low  shores  of  this  primitive  Gulf 
of  Mexico  were  covered  with  a  warm  climate  strand  flora  and  con- 
tained but  few  representatives  of  our  familiar  trees.  A  great 
variety  of  tropical  types  had  invaded  that  region  from  the  south, 
many  of  which  like  the  bread-fruit  and  Nipa  palm  are  no  longer 
found  anywhere  in  the  Western  Hemisphere. 


22 


TREE    ANCESTORS 


Fig.  3.  Map  Showing  the  Maximum  Extent  of  Eocene  Seas  on  the  North 
American  Continent 


LATER   GEOLOGICAL  HISTORY   OF   NORTH   AMERICA  23 

Toward  the  close  of  the  Eocene  and  in  the  early  OHgocene  the 
climate  seems  to  have  reached  its  maximum  of  warmth — the  forests 
along  the  Gulf  coast  are  sub-tropical,  coral  reefs  are  found  in 
Georgia  and  temperate  forests  covered  Alaska,  Greenland  and  even 
the  lands  as  far  north  as  Spitzbergen.  At  this  time  there  was  again 
a  free  interchange  of  Hfe,  both  animal  and  vegetable,  between 
North  America,  Europe  and  Asia. 

With  the  continued  elevation  of  the  Rocky  Mountain  region 
great  changes  in  cHmatic  conditions  were  brought  about  in  the  West 
and  the  plains  type  of  country  became  developed  over  large  areas. 
This  was  important  since  it  represents  the  beginning  of  that  cleavage 
between  the  modem  Atlantic  and  the  Pacific  forest  and  general 
floral  provinces  which  exhibit  so  many  striking  contrasts.  The 
accompanying  map  (fig.  4)  shows  the  extent  of  the  OHgocene  seas 
and  the  area  of  the  plains  country  which  was  called  into  existence 
by  the  rising  mountains  which  cut  off  the  moisture  laden  winds 
from  the  Pacific  and  caused  the  forests  to  be  gradually  replaced 
by  the  prairies. 

During  the  succeeding  Miocene  and  Pliocene  periods  many  identi- 
cal trees  persisted  in  the  East  and  the  West  but  they  were  effectually 
cut  off  from  intercommunication  except  in  the  far  North  by  the 
central  arid  region  and  each  area  has  henceforward  had  a  history 
entirely  its  own. 

Fossil  floras  of  these  later  Tertiary  times  are  rather  rare  and  are 
only  found  in  local  deposits  in  some  favorably  situated  mountain 
lake  basin  or  river  flood  plain  or  in  the  chance  burial  of  drifted 
vegetable  debris  in  the  predominantly  marine  deposits  of  the  con- 
tinental borders.  The  most  extensive  of  these  local  floras  is  that 
preserved  at  Florissant,  Colorado,  where  successive  showers  of 
volcanic  ashes  have  preserved  remnants  of  a  large  lake  and  river- 
side upland  flora.  The  cHmate  appears  to  have  been  somewhat 
warmer  than  it  is  at  the  present  time  in  the  heart  of  the  Rockies 
and  this  flora  includes  species  of  figs,  magnolias,  soapberry,  persim- 
mon, ailanthus,  beech,  elm,  maple,  locust  and  oak.  Libocedrus 
or  incense  cedar  is  stiU  present  and  the  sequoia  trunks  which  were 
silicified  at  the  same  time  that  the  foliage  was  preserved  in  the 


^'X!SaU  "'''''" 


24 


TREE    .\NCESTORS 


Fig.  4..  ]\Iap  Shouixg  Oligocene  Seas  on  the  North  American 
Continent 


I,ATER   GEOLOGICAL  HISTORY   OF   NORTH    AMERICA  25 

lake  laid  volcanic  ashes  show  that  these  Colorado  sequoias  rivalled 
in  size  the  present  big  trees  of  California.  Many  additional  genera 
testify  to  the  changes  that  have  taken  place  in  the  flora  of  the  Rocky 
Mountain  region  since  Miocene  times. 

A  few  PKocene  plants  have  been  preserved  in  New  Jersey  and 
along  the  Gulf  coast  in  Alabama.  These  show  that  the  forests  in 
those  regions  were  much  like  they  are  today  with  some  survivors 
from  the  older  days  that  have  since  disappeared. 

The  Tertiary  period  was  succeeded  by  the  Quaternary  period 
which  corresponds  roughly  with  what  is  called  the  Pleistocene  and 
which  in  turn  corresponds  approximately  to  the  glacial  period  or 
Ice  Age.  The  Pleistocene  is  often  divided  into:  (1)  an  earher  or 
preglacial  stage  which  shows  in  general  a  minghng  of  warm  tem- 
perate, and  cool  temperate  forms;  (2)  a  middle  or  glacial  stage  with 
alternating  interglacial  periods  in  some  of  which  the  climate  was 
above  the  normal  modern  optimum  for  the  same  latitudes,  and 
during  which  the  biological  record  shows  a  succession  of  forest, 
field,  barren  ground,  steppe,  tundra,  and  arctic  types  in  some  more 
northern  or  montane  regions;  with  increasing  glaciation  and  the 
same  succession  in  an  inverse  order  with  the  retreat  of  the  glaciers ; 
and  finally  there  is  (3). the  so-called  postglacial,  late  or  Upper 
Pleistocene  stage  which  merges  with  the  Recent,  and  during  which 
our  modern  flora  assumed  its  present  distribution.  The  post- 
glacial and  Recent  may  be  compared  with  the  previous  interglacial 
stages  and  there  are  many  arguments  in  favor  of  considering  that 
we  are  now  living  in  a  fourth  interglacial  period  since  the  time  that 
has  elapsed  since  the  last  ice  sheet  covered  northeastern  North 
America  is  less  than  the  duration  of  some  of  the  previous  interglacial 
periods. 

Geologically  the  Pleistocene  deposits  are  typically  glacial  in  the 
north  and  in  the  more  elevated  mountainous  regions,  namely, 
boulder  clay  or  drift,  gravels,  till,  loess,  peat  bogs;  and  in  the  South, 
lake,  river,  eolian,  swamp,  cave  and  marine  terrace  deposits.  In 
the  North  the  floral  record  is  still  largely  hidden  in  the  for  the  most 
part  unstudied  peat  bogs.  Farther  south  it  is  furnished  by  the 
river  clays  and  prehistoric  cypress  swamps. 


26  TREE   ANCESTORS 

A  moment's  reflection  will  convince  the  reader  that  an  ice  cap 
like  that  of  modern  Greenland  with  centers  of  radiation  in  Labrador, 
west  of  Hudson  Bay  and  in  the  Cordilleras  and  extending  south- 
ward to  New  Jersey  and  Kentucky  was  a  most  profound  factor 
affecting  the  present  flora  of  North  America  both  as  regards  the 
present  distribution,  the  extinction  of  old,  and  the  evolution  of 
new  types.  The  effect  of  glaciation  was  even  more  marked  in 
Europe  than  in  America  for  in  the  former  the  mountain  chains 
run  in  an  east-west  direction  and  with  the  Mediterranean,  Black 
and  Caspian  seas  effectually  blocked  the  retreat  of  the  flora  to  the 
southward.  Hence  there  are  many  types  of  trees  that  are  exclu- 
sively American  and  Asian  in  the  existing  flora  that  were  common 
to  Europe  in  pre-Pleistocene  and  a  part  of  Pleistocene  times.  Some 
of  these  are  the  magnolia,  locust,  sassafras,  bald  cypress,  black 
walnut,  butternut,  etc. 

The  accumulated  data  are  quite  insufficient  to  enable  us  to  trace 
the  waves  of  plant  and  animal  life  that  swept  back  and  forth  across 
North  America  with  the  fluctuations  of  the  cHmate.  We  know  that 
the  sweet  birch  and  the  larch  got  dovm  into  Georgia  during  an 
advance  of  the  ice  sheet  and  we  have  found  spruce  cones  in  the 
Pleistocene  deposits  at  Chicago.  We  find  the  red  bud,  osage  orange 
and  other  warm  temperate  types  as  far  north  as  Toronto,  Canada, 
during  an  interglacial  period,  and  specimens  of  a  fig  in  fruit  has 
been  found  in  interglacial  deposits  as  far  north  as  the  Kootenai 
Valley  in  British  Columbia.  We  have  such  facts  as  the  presence 
of  fossil  wood  of  Pseudotsuga  near  Kansas  City,  Missouri,  and  the 
wood  of  the  black  spruce  (Picea  mariana)  and  the  cones  of  the 
white  spruce  {Picea  canadensis)  beneath  the  drift  of  the  Kansas 
ice  sheet  or  second  glacial  advance  in  Iowa. 

Away  from  the  ice  covered  regions  the  climate  was  probably 
not  severe  and  if  there  was  any  pronounced  secular  lowering  of 
temperatures  it  appears  to  have  been  offset  by  increased  humidity 
and  the  dense  stands  of  timber  in  the  lowlands.  We  infer  this 
from  the  fact  that  in  deposits  of  Pleistocene  age  in  the  region  to 
the  southward  of  the  ice  sheet  scarcely  ever  do  the  fossil  plants 
indicate  any  appreciable  differences  from  present  day  temperatures. 


LATER    GEOLOGICAL    HISTORY    OF    NORTPI    AMERICA  27 

It  seems  probable  that  the  great  majority  of  our  arborescent  flora 
or  forest  trees  were  already  in  existence  before  the  close  of  the 
Pleistocene,  if  not  in  the  preceding  Pliocene,  such  changes  as 
have  occurred  since  that  time  relating  almost  entirely  to  their 
distribution. 

The  making  available  for  occupation  of  large  areas  covered  by 
the  ice  sheet  or  submerged  along  the  continental  border  and  the 
resulting  complexity  of  glacial  soils  was  doubtless  a  great  stimulus 
to  evolutionary  activity,  which  was,  however,  confined  almost 
entirely  to  the  herbaceous  vegetation. 

In  the  preceding  very  brief  sketch  the  aim  has  been  to  convey 
in  a  concrete  manner  the  cardinal  fact,  often  overlooked,  that  our 
present  forest  flora  is  but  one  of  many  that  have  flourished  in  this 
country  and  that  its  beginnings  may  be  traced  back  several  millions 
of  years,  rather  than  to  present  a  detailed  picture  of  the  floral 
history  of  North  America  since  the  Cretaceous.  No  attempt  has 
been  made  to  make  the  following  sketches  exhaustive  even  for  the 
forms  that  are  discussed,  and  while  the  separate  discussion  of  the 
different  forest  trees  necessitates  a  certain  amount  of  repetition 
tliis  will  serve  to  amplify  and  fix  the  facts  of  the  foregoing  brief 
outhne  of  the  later  history  of  our  continent  and  its  relations  to 
the  other  continents. 


CHAPTER  VI 

The  Present  Forests  of  North  America 

The  United  States  occupies  the  second  place  among  the  nations 
of  the  Xorthern  Hemisphere  in  the  extent  of  its  forests,  Russia 
having  first  rank  and  Canada  third,  so  that  North  America  as  a 
whole  probably  ranks  first  in  forest  resources  among  the  northern 
continents. 

North  America  may  be  conveniently  divided  for  a  consideration 
of  its  forests  into  four  major  regions.  These  are:  (1)  A  northern 
sub-Arctic  region;  (2)  a  temperate  Atlantic  region;  (3)  a  temperate 
Pacific  region,  and  (4)  a  Central  American-Antillean  region.  Each 
of  these  regions  naturally  embrace  a  great  variety  of  soils,  climate 
and  topography  and  consequently  a  variety  of  different  forest 
associations.  All  become  modified  toward  their  limits  and  are  not 
to  be  sharply  bounded  except  by  broad  and  gradually  changing 
transition  zones,  but  in  their  typical  expression  they  are  exceedingly 
well  marked. 

The  Northern  region  is  essentially  a  part  of  that  Holarctic  belt 
of  vegetation  that  encircles  the  globe  in  the  region  bordering  the 
Arctic  tundra.  In  North  America  it  constitutes  a  broad  belt  of 
sub-Arctic  (Hudsonian)  woodland  extending  from  the  tundra  or 
northern  limit  of  tree  growth  southward  to  a  rather  indefinite 
boundary  at  about  latitude  53°  and  hence  covering  between  10^ 
and  15°  of  latitude.  It  stretches  across  the  continent  from  southern 
Labrador,  south  of  Hudson  Bay  and  then  northwestward  to 
within  the  Arctic  Circle  in  the  lower  Mackenzie  basin  and  in 
northern  Alaska,  reaching  the  Pacific  at  Cook  Inlet. 

This  whole  area  receives  an  ample  rainfall  except  toward  its 
southwestern  limits.  It  occupies  throughout  nearly  its  whole 
extent  a  glaciated  area  with  innumerable  lakes,  streams,  and  ex- 
tensive swamps,  especially  in  the  region  between  Hudson  Bay  and 
Lake  Winnipeg,  where  the  country  is  largely  swampy  with  a  tree 

28 


PRESENT    FORESTS    OF    NORTH    AMERICA  29 

growth  of  willows  and  tamarack.  The  topography  and  low  mean 
temperatures  serve  to  limit  the  number  of  arborescent  species, 
which  is  also  influenced  by  the  character  of  the  soil,  and  as  the 
more  northerly  parts  of  the  belt  are  reached  the  forests  become  more 
and  more  open  and  stunted  until  the  black  spruce  becomes  a  shrub 
associated  with  dwarf  willows  and  birches. 

Floristically  this  northern  region  has  been  divided  into  the  fol- 
lowing four  illy  defined  and  not  clearly  marked  districts:  (1)  The 
Labrador  District;  (2)  the  Hudson  Bay  District;  (3)  the  Mackenzie 
District;  and  (4)  the  Alaska  District.  As  regards  the  tree  species 
these  districts  are  not  distinct  for  of  the  eight  common  types  found 
in  Labrador  the  following  five  range  from  the  Atlantic  to  the  Pacific: 
the  white  spruce  {Picea  canadensis) ,  the  black  spruce  (Piceamariana) , 
the  canoe  birch  {Betula  papyrifera) ,  the  aspen  (Populus  tremnloides) , 
the  balsam  poplar  {Populus  balsamifera).  The  tamarack  {Larix 
laricina)  ranges  west  as  far  as  the  Mackenzie  River:  the  jack 
pine  {Piniis  divaricata)  and  the  balsam  fir  {Abies  halsamea)  range 
west  to  the  Mackenzie  River  and  are  replaced  in  Alaska  by  the 
lodgepole  pine  {Pimis  mnrrayana)  and  the  alpine  fir  {Abies  lasio- 
carpa)  respectively. 

The  forests  show  local  variations  from  place  to  place  dependent 
upon  the  temperature,  altitude  and  soil.  In  general  the  stand 
becomes  larger  and  closer  southward  and  more  open  and  stunted 
northward.  For  example  in  Labrador  the  forests  are  continuous 
in  the  southern  part  decreasing  northward  until  at  latitude  55° 
the  trees  are  confined  to  lake  margins  and  river  valleys.  Here  black 
spruce  is  the  most  abundant  tree  and  constitutes  fully  90  per  cent 
of  the  forest  on  sandy  soils,  both  wet  and  dry,  of  the  pre-Paleozoic 
area.  The  tamarack  is  always  an  inhabitant  of  cold  swamps  and 
in  the  region  southwest  of  Hudson  Bay  tamarack  swamps  and  wil- 
low thickets  cover  most  of  the  country.  The  aspen  is  found  on 
ridges  of  till  in  the  east,  it  borders  the  northern  extension  of  the 
prairie  in  Athabasca  and  on  the  plains  along  the  Mackenzie  River. 
The  balsam  poplar  frequents  the  heavy  clay  soils  in  the  wide 
valleys  and  river  bottoms  and  tends  to  be  run  out  in  places  by  the 
white  spruce  which  also  clothes  the  low  divides.     The  canoe  birch 


30  TREE   ANCESTORS 

forms  glade  thickets,  and  most  of  the  bottom  lands  support  thickets 
of  shrubby  willows  {Salix  adenophylla,  halsamifcra,  chlorophylla, 
etc.).  The  treeless  moors  are  characterized  by  dwarf  willows 
{Salix  myrtilloides)  and  dwarf  birches  {Be tula  nana)  and  by  Cassan- 
dra calyculata,  Kalmia  glauca,  Ledum  palustre,  etc.  Although  the 
forests  of  this  northern  region  are  of  little  economic  importance  at 
the  present  time  in  the  thinly  settled  condition  of  most  of  this 
vast  region  they  are  destined  to  be  of  incalculable  value  for  fuel 
and  domestic  construction  and  probably  for  pulpwood,  mine  props 
and  other  purposes  when  the  country  shall  have  become  opened 
up  and  more  thickly  settled. 

THE    ATLANTIC    REGION 

The  Atlantic  region  comprises  that  part  of  North  America  ex- 
tending from  about  latitude  53°  north  southward  to  the  Gulf  of 
Mexico  and  from  the  Atlantic  seaboard  westward  to  the  prairie 
country  of  the  Mississippi  valley,  or  to  about  the  95th  meridian. 
This  region  includes  a  very  great  variety  of  topography,  climate, 
and  soils,  covering  as  it  does  more  than  40°  of  longitude  and  more 
than  25°  of  latitude.  Along  its  northern  margin  the  transition  to 
the  sub-Arctic  region  is  fairly  well  marked,  but  the  western  bound- 
ary is  to  be  found  somewhere  in  the  transition  zone  from  forest 
to  prairie — grass  lands  extending  far  to  the  east  in  Illinois  and  the 
eastern  forest  extending  long  distances  to  the  west  along  the  valleys 
of  the  principal  streams  of  the  prairie  states. 

Physiographically  tliis  vast  area  includes  the  Laurentian  Upland, 
the  Atlantic  Plain,  the  Appalachian  Highlands,  the  Interior  Low 
Plateau,  and  parts  of  the  Central  Lowlands  and  the  Interior  High- 
lands (Ozark  and  Ouchita).^  The  Atlantic  region  may,  however, 
be  divided  into  three  areas  which  are  fairly  well  marked  by  the 
character  of  the  woodland.  These  are:  (1)  the  Northern  Ever- 
green Coniferous  forest;  (2)  the  Deciduous  or  Hardwood  forest, 

^  The  terminology  is  that  of  the  Committee  of  the  Association  of  American 
Geographers.  Fenneman,  N.  M.,  Annals  Assn.  Am.  Geog.,  vol.  6,  pp.  19-98, 
1917. 


PRESENT   FORESTS    OF   NORTH    AMERICA  31 

and  (3)  the  Southeastern  Evergreen  Coniferous  forest.  The  char- 
acter of  the  topography,  soils  and  cHmate  as  well  as  the  geological 
history  of  the  forests  have  resulted  in  interfingered  areas  and  out- 
liers of  one  type  within  the  area  of  another,  and  their  boundaries 
are  in  most  cases  covered  by  a  broad  transition  zone  between  forest 
and  prairie  or  between  evergreen  needle  leaved  and  broad  leaved 
deciduous  forest. ^ 

The  Northern  Evergreen  Coniferous  forest  extends  from  New- 
foundland west  to  the  96th  meridian,  and  from  James  Bay  south- 
ward beyond  the  Great  Lakes.  On  the  east  its  southern  limits 
include  most  of  Maine  and  areas  in  New  Hampshire,  Vermont 
and  New  York,  with  a  southern  extension  along  the  higher  Appalach- 
ian ridges  to  West  Virginia,  and  isolated  patches  to  the  southward 
along  these  mountains  in  the  Great  Smoky  Mountain  region  along 
the  North  Carolina-Tennessee  boundary. 

In  its  typical  development  this  forest  is  characterized  by  pure 
or  nearly  pure  stands  of  needle  leaved  conifers  among  which  the 
white  pine  {Pinus  strohus)  is  the  most  important  if  not  the  most 
widely  distributed  tree.  Virgin  stands  range  60  to  125  feet  in 
height  and  vary  from  heavy  stands  with  a  shaded  floor  almost 
devoid  of  undergrowth  to  more  open  stands  with  an  undergrowth 
of  deciduous  under-trees  and  shrubs.  Nearly  pure  stands  of  the 
black  spruce  are  also  important  features  of  this  region,  especially 
toward  the  north. 

Within  this  area  the  hemlock  (Tsiiga  canadensis),  the  arbor  vitae 
(Thuja  occidentalis)  the  basswood  (Tilia  americana),  the  black  ash 
{Fraxinus  nigra),  the  white  ash  {Fraxinus  americana),  the  sugar 
maple  (Acer  saccharum)  and  several  species  of  birch  {Betiila)  and 
elm  (Ulmus)  reach  their  northern  limits  and  the  center  of  their 
maximum  distribution.  The  hickories  and  oaks,  so  characteris- 
tic of  the  deciduous  forests  of  the  Atlantic  region,  reach  their 
northern  limits  of  distribution  in  this  area  of  Northern  Evergreen 
Coniferous  forest  as  do  the  chestnut  {Castanea  dentata),  the  horn- 
beam {Ostrya  virginiana),  the  sassafras  (Sassafras  sassafras),  the 

2  See  Shreve,  F.,  A  Map  of  the  Vegetation  of  the  United  States.  Geograph- 
ical Review,  vol.  3,  pp.  119-125,  pi.  3,  1917. 


32  TREE    ANCESTORS 

tulip-trce  {Liriodendron  tidipifera),  the  cucumber- tree  (Magnolia 
acuminata),  the  red  cedar  {Juniperus  virginiana),  the  black  gum 
{J^yssa  sylvatica),  the  sycamore  (Platanus  occidentalis) ,  the  witch 
hazel  {Hamamelis  virginiana),  the  beech  {Fagus  atro pnnicea) , 
and  other  important  deciduous  tree  species. 

Commercially  this  region  has  been  the  scene  of  very  extensive 
lumbering  operations  and  its  advantageous  situation  enable  it  to 
still  furnish  an  enormous  annual  production. 

TIIE  DECIDUOUS   FOREST 

The  Deciduous  or  Hardwood  forest  area  of  the  Atlantic  region 
extends  with  varying  elements  from  southern  Maine  and  northern 
New  York  to  Texas,  and  from  about  the  fall-line  of  the  South  At- 
lantic Coastal  Plain  inland  across  the  uplands  to  the  Ohio  and  the 
lower  Mississippi  drainage  basins,  the  western  Kmit  being  deter- 
mined by  the  lessened  rainfall,  the  former  prevalence  of  forest 
fires,  the  force  of  the  winds  and  the  difficulty  of  regaining  a  foot- 
hold in  the  compactly  sodded  prairie  region  where  the  geological 
record  shows  that  a  similar  forest  once  held  undisputed  sway. 
This  western  boundary  is  essentially  a  broad  transition  zone,  the 
woodland  becoming  more  and  more  open  and  finally  becoming 
restricted  to  the  river  bottoms.  The  extreme  western  boundary 
runs  through  the  eastern  Dakotas,  Nebraska,  Kansas,  etc.,  but 
the  actual  boundary  of  the  forested  area  where  the  woodland  covers 
more  than  20  per  cent  of  the  area  extends  from  the  southern  end 
o^  Lake  Michigan,  across  southern  Ilhnois,  southeastern  Missouri 
and  includes  parts  of  Arkansas,  Oklahoma  and  Texas.  Toward 
both  its  northern  and  its  southern  limits  the  Deciduous  forest  is 
bordered  by  a  transition  zone  of  mixed  deciduous  and  coniferous 
trees. 

In  typical  stands  the  Deciduous  forest  comprises  broad  leaved 
species  of  oaks,  hickories,  walnuts,  ashes,  maples,  magnolias, 
cherry,  tulip-tree,  sycamore,  beech,  linn,  chestnut,  etc.  On  the 
slopes  of  the  southern  Appalachians,  in  the  valley  of  the  lower 
Ohio  and  in  the  valley  of  the  lower  Red  River,  these  deciduous  types 
attain  their  greatest  variety  as  well  as  their  maximum  development. 


PRESENT  FORESTS   OF   NORTH    AMERICA  33 

Outliers  of  the  deciduous  forest  occur  on  the  Michigan  peninsu- 
las. The  southern  boundary  extending  from  North  Carolina  to 
Mississippi  and  reappearing  west  of  the  river  of  that  name  in 
Arkansas,  Louisiana  and  Texas,  passes  gradually  into  a  transition 
zone  where  there  is  a  nearly  equal  commingling  of  the  deciduous 
and  the  evergreen  species  of  the  adjacent  regions.  Locally,  as 
determined  by  soil  conditions,  nearly  pure  stands  of  one  of  the 
other  will  dominate.  The  commonest  conifers  in  such  situations 
are  the  loblolly  pine  {Pinus  taeda)  or  scrub  pine  {Pinus  echinata) 
while  the  most  common  deciduous  species  are  the  post  oak  {Quercus 
minor),  the  Spanish  oak  {Quercus  digitata)  and  the  blue  jack  oak 
{Quercus  hrevifolia) . 

The  southeastern  Evergreen  Coniferous  forest  extends  from  the 
mouth  of  the  Chesapeake  Bay  southward  along  the  Coastal  Plain 
of  the  Atlantic  and  Gulf  states  in  a  belt  from  100  to  200  miles  in 
width  until  it  is  interrupted  by  the  bottom  lands  of  the  Mississippi 
River,  reappearing  in  Louisiana  and  southeastern  Texas.  Outside 
the  river  bottoms  with  their  variety  of  deciduous  species  this  belt 
is  characterized  by  the  extensive  areas  of  nearly  pure  but  open 
stands  of  the  long  leaf  pine  {Pinus  palustris)  or  the  cuban  pine 
{Pinus  carihaea).  The  coastal  margin  is  characterized  by  the 
live  oak,  the  sand  pine,  the  palmetto,  etc.,  while  the  bottoms  and 
shallow  ponds  contain  various  gums,  hickories,  water  oaks,  ashes 
and  the  sycamore  and  bald  cypress — the  latter  and  the  long  leaf 
pine  being  undoubtedly  the  most  valuable  commercially. 

THE    PACIFIC    REGION 

The  Pacific  forest  region  may  be  considered  as  comprising  all  of 
western  North  America  between  the  Rocky  Mountain  front  and 
the  Pacific  coast.  This  is  a  vast  area  and  one  containing  an  un- 
usual variety  of  topography,  climate  and  soils.  The  major  in- 
fluence that  has  determined  the  presence  or  the  absence  and  the 
relative  density  of  tree  growth  is  the  peculiar  distribution  of  the 
chmate  as  expressed  more  especially  in  the  rainfall.  The  north- 
west coast  from  northern  California  northward  is  a  region  of  very 
heavy  rainfall  and  consequently  it  has  a  dense  forest  cover  of  large 


34  TREE    ANCESTORS 

evergreen  conifers.  Along  the  coast  to  the  southward  the  rainfall 
decreases  progressively  until  in  southern  CaHfornia  land  tempera- 
tures so  far  exceed  ocean  temperatures  that  more  or  less  of  the 
year  is  without  precipitation.  The  north  and  south  trend  of  the 
mountain  ranges  govern  the  rainfall  of  the  interior,  consequently  a 
large  part  of  the  country  except  the  higher  chains  are  entirely  or 
nearly  rainless.  Woodlands  are  consequently  confined  to  the  flanks 
and  summits  of  the  mountains.  The  resulting  effects  upon  the 
vegetation  are  succinctly  summarized  in  Shreve's  (op.  cit.)  segre- 
gation of  these  arid  or  semi-arid  areas  into  seven  units.  These  are: 
(1)  The  California  Desert — a  region  of  low  and  open  small  leaved 
shrubs  like  the  creosote  bush  (Covillea);  (2)  the  Great  Basin 
Desert^a  region  of  stunted  shrubs,  among  which  the  dominant 
plant  is  the  sage  bush  (Artemisia) ;  (3)  the  Arizona  Desert — a  re- 
gion of  mixed  small  leaved  shrubs  such  as  the  creosote  bush,  and 
the  palo  verde  (Parkinsonia),  succulent  stemmed  cacti,  such  as 
Carnegiea  and  Opuntia;  (4)  the  Texas  Desert  of  mixed  small 
leaved  shrubs  and  succulent  or  semi-succulents  such  as  Agave, 
Dasylirion  and  Yucca;  (5)  the  Cahfomia  semi-desert,  a  region  of 
great  diversity,  ranging  from  open  woodland,  chiefly  evergreen 
oaks,  through  chaparral  to  true  desert;  (6)  the  Texas  semi-desert, 
a  region  of  interspersed  grassland  and  scrub  made  up  largely  of 
mesquite  (Prosopis)  with  some  succulents;  (7)  desert  to  Grassland 
Transition,  a  region  of  grassland  with  ephemeral  or  root  perennial 
herbs  and  more  or  less  succulent  or  semi-succulent  types. 

The  forests,  as  distinct  from  the  vegetation  areas,  are  considered 
by  Sargent'  to  be  separable  into  three  regions  which  he  terms: 
(1)  The  Coast  forest;  (2)  the  Interior  forest;  and  (3)  the  Mexican 
forest. 

The  Coast  forest  is  the  heaviest,  although  not  the  most  varied, 
forest  on  the  continent.  It  extends  along  the  coast  from  about 
latitude  60°  to  about  latitude  40°,  ranging  eastward  at  the  Inter- 
national boundary  following  the  eastward  extension  of  heavy  rain- 

^  Sargent,  C.  S.,  Forest  Trees  of  North  America.  Tenth  Census,  vol.  9, 
1884.  This  author's  fourth  category,  the  Northern  forest,  has  already  been 
discussed  as  the  western  part  of  the  sub-Arctic  forest. 


PRESENT   FORESTS    OF   NORTH    AMERICA  35 

fall  over  the  Gold,  Selkirk,  Coeur  d'Alene,  Bitter  Root  and  other 
interior  ranges.  It  consists  largely  of  a  few  coniferous  species  and 
nowhere  do  broad  leaved  deciduous  trees  form  extensive  stands 
as  they  do  in  the  Atlantic  region.  The  latter  are  generally  con- 
fined to  the  stream  valleys  and  are  of  slight  importance  from  the 
viewpoint  of  the  timber  industries.  Towards  the  north  the  yellow 
cedar  (Chamaecy parts  nootkatensis) ,  the  Sitka  spruce  {Picea  stichen- 
sis)  and  the  hemlock  {Tsuga  heterophylla)  are  the  most  important 
trees.  To  the  southward  more  southern  forms  gradually  assume 
a  predominance. 

The  "red  fir"  {Pseudotsiiga  nohilis  and  magnifica)  is  the  prevailing 
tree  in  the  vicinity  of  Puget  Sound  and  southward  in  Washington 
and  Oregon.  The  "red  cedar"  {Thuja  plicata),  white  fir  (Abies 
grandis),  mountain  hemlock  {Tsuga  pattoniana)  and  red  wood 
{Sequoia  sempervirens)  are  also  abundant  and  of  large  size.  The 
river  bottoms  contain  heavy  growths  of  maple,  cottonwood,  ash, 
etc.,  and  the  narrower  interior  valleys  an  open  growth  of  oak. 
Farther  south  the  sugar  pine  (Pinus  lajnhertiana) ,  Libocedrus  and 
Chamaecyparis  lawsoniana  add  variety  and  value  to  the  Coast 
forest,  while  along  the  Cahfornia  coast  between  the  summit  of  the 
Coast  Range  and  the  ocean  and  extending  to  latitude  37°,  the 
redwood  is  the  predominant  tree.  Here  several  species  of  singu- 
larly restricted  distribution  are  represented  {Cupressus  macro- 
car  pa,  Pinus  radiata,  Abies  venusta,  Pinus  torreyana,  Tumion 
calif ornicum,  etc.). 

South  of  the  35th  parallel  the  increasingly  arid  climate  checks 
the  coast  forest  and  the  scanty  woodland  of  the  higher  elevations 
of  the  Coast  Range  farther  south  are  of  the  Sierra  rather  than  the 
Coast  type.  A  dense  forest  covers  the  western  slopes  of  the  Sierra 
Nevada.  The  characteristic  species  are  the  sugar  pine,  yellow 
pine,  red  fir,  Abies,  Libocedrus,  the  giant  Sequoia,  with  valley  for- 
ests of  scattered  oaks.  The  eastern  slopes  are  characterized  by  a 
variety  of  large  and  valuable  pines. 

The  Interior  forest  extends  from  the  sub-Arctic  forest  region  of 
the  north  southward  into  Mexico,  and  is  confined  to  the  slopes  and 
canons  of  the  numerous  mountain  ranges — ^the  valleys  except  for 


36  TREE   ANCESTORS 

the  immediate  river  bottoms  are  practically  treeless.  These  for- 
ests are  destitute  of  variety  and  for  the  most  part  stunted.  They 
are  characterized  by  cottonwood  (Populus),  nut  pine  {Pinus  cdulis), 
white  iir  {Ahics  concolor),  lodgepole  pine  {Pinus  murrayana), 
various  spruces  {Picea  Engelmanni  and  parryana),  etc. 

The  greater  part  of  Mexico,  including  Baja  or  Southern  Cali- 
fornia, is  occupied  by  vegetational  areas  which  are  the  southward 
continuation  of  those  of  the  southwestern  United  States.  Nowhere 
down  to  latitude  22°  can  the  term  forest  be  apphed  to  the  plant 
cover  except  in  the  higher  elevations  of  the  Eastern  and  Western 
Sierra  Madre  that  bound  the  Anahuac  Desert  Plateau.  Above 
7000  feet  there  are  open  pine  forests  {Pinus  arizonica,  chihuahuana, 
micro phylla,cemhroides)  and  clumps  of  scrub  oak  {Quercus  gisea  etc.), 
with  aspens  and  a  few  broad  leaved  temperate  types.  At  about 
latitude  23°  the  broken  transverse  volcanic  chains  of  high  moun- 
tains strike  at  almost  right  angles  to  the  trends  of  the  Sierra  Madre. 
This  is  the  region  termed  volcanic  by  Thayer*  and  United  Cordil- 
leran  by  Harshberger.  The  higher  elevations  are  covered  with 
open  pine  forests  and  the  subordinate  slopes  by  oak  forests  with  a 
mixture  of  other  broad  leaved  temperate  types  and  some  stragglers 
from  the  tropical  forests  to  the  southward.  The  Gulf  Coastal 
Plain,  more  or  less  covered  with  chaparral  in  its  northern  extent 
passes  gradually  into  a  typical  tropical  forest  toward  the  south, 
while  on  the  West  Coast  the  Jaliscan  Coastal  Plain  furnishes  wild 
figs  and  Taxodium  in  the  bottoms  and  chaparral  on  the  divides, 
with  open  growths  of  oak  and  pine  at  higher  elevations. 

CENTRAL  AMERICAN  ANTILLEAN  REGION 

This  is  somewhat  of  a  composite  of  insular  and  continental 
areas  with  typical  tropical  lowland  forests  and  with  a  few  repre- 
sentatives of  temperate  types  in  the  higher  uplands.  It  cannot  be 
properly  described  without  going  into  more  detail  than  is  warranted 
in  the  present  connection,  and  while  it  is  a  region  of  surpassing 

^Thayer,  Physiographic  Provinces  of  Mexico.  Jour.  Geol.,  vol.  24,  pp. 
61-94,  1915.  Harshberger,  J.  W.,  Phytogeographic  Survey  of  North  America, 
1911. 


PRESENT   FORESTS   OF   NORTH    AMERICA  37 

interest  both  in  regard  to  its  present  botanical  features  and  their 
bearing  on  the  geologic  history  of  the  North  American  flora,  these 
problems  do  not  enter  to  any  large  degree  into  a  discussion  of  the 
particular  forest  trees  considered  in  the  present  work. 

This  region  comprises  tropical  North  America  which  includes 
all  of  Central  America;  the  Antilles,  Bahamas  and  Bermudas; 
and  the  narrow  Atlantic  and  Pacific  Coastal  plains  of  Mexico. 
Practically  the  only  types  of  this  region  that  reach  the  United  States 
are  found  in  the  narrow  strips  along  the  coast  and  keys  of  peninsu- 
lar Florida  which  extend  northward  to  about  Cape  Malabar  on  the 
East  Coast  and  to  Tampa  Bay  on  the  West  Coast.  This  flora  is 
rich  in  composition  but  is  here  of  slight  economic  importance. 
Some  of  the  sub-tropical  forms  do  not  reach  these  limits  and  others 
extend  a  degree  or  two  farther  north.  Among  the  more  important 
trees  are  the  royal  palm,  mahogany,  sea  grape,  Jamaica  dog^vood, 
machineel,   mangrove,   etc. 

Throughout  the  Bahamas  and  Bermudas  true  forests  are  absent 
and  are  replaced  by  coppice  growths  of  a  variety  of  tropical  species. 
The  larger  islands  of  the  Antilles,  at  one  time  probably  largely  in 
forest,  have  suffered  greatly  from  agricultural  encroachments,  and 
former  primitive  practices  of  making  new  clearings  every  few  years, 
which,  combined  with  charcoal  burning  and  the  general  failure  to 
regard  the  forests  as  anything  but  an  enemy  of  man,  have  resulted 
in  limiting  the  forest  to  the  more  inaccessible  or  less  readily  culti- 
vated parts  of  the  islands,  as  is  conspicuously  the  case  in  Porto 
Rico.  In  Cuba  the  largest  of  the  Antilles,  savannas  alternate  with 
open  forests  of  Ceiba,  Bursera,  Spondias,  Cedrela,  Swietenia 
Pithecolobium,  Lysiloma,  Lonchocarpus,  and  many  other  tropical 
species.  Tropical  jungle  or  rain  forest  is  less  extensive  than  on 
the  mainland,  but  is  more  or  less  developed  on  all  of  the  larger 
islands. 

Central  America  may  be  divided  into  three  principal  botanical 
regions  although  the  general  type  of  the  forests,  disregarding  indi- 
vidual elements,  is  much  the  same  throughout  and  has  been  simi- 
larly more  or  less  marred  by  primitive  agriculture  dating  back  to 
a  time  remote  enough  to  permit  so-called  virgin  forests  to  cover 


38  TREE    ANCESTORS 

its  sites,  and  modified  by  the  great  extension  of  organized  culti- 
vation of  bananas,  cane,  coffee,  rubber,  citrus  fruits,  etc. 

These  three  regions  are  the  Costa  Rican,  Guatemalan  and  South 
]\[exican  Gulf  regions.  The  Costa  Rican  region  comprises  Panama, 
Costa  Rica  and  southern  Nicaragua.  Vast  and  dense  tropical  rain 
forests  or  impenetrable  jungles  once  covered  the  Atlantic  water- 
shed, which  includes  most  of  the  area  since  the  divide  is  near  the 
Pacific  coast.  Many  South  American  types  are  present,  as  for 
example,  Podocarpus  (taxifolia  and  salicifolia)  which  replaces  the 
pines  of  the  mountains  of  Guatemala.  Oaks  are  still  abundant 
above  7000  feet,  but  most  of  the  North  American  broad  leaved 
types  that  are  represented  reach  their  southern  lunits  in  Costa 
Rica.  The  rain  forest  is  dense  and  almost  infinitely  varied — the 
trees  with  buttressed  roots,  the  undergrowth  thick,  and  a  great 
variety  of  lianas  and  epiphytes.  Some  of  the  commoner  trees  are 
Ceiba,  Hura,  Cedrela,  Haematoxylon,  Erythrina,  Guaiacum, 
Castilloa,  Achras,  Pithecolobium,  Leucaena,  Inga,  Ficus,  etc., 
with  a  great  variety  of  palms. 

The  Guatemalan  region,  which  includes  the  state  of  Cliiapas 
(Mexico),  Honduras,  Salvador,  Guatemala,  and  northern  Nicara- 
gua, is  similar  to  the  preceding  except  that  the  oaks  are  more 
abundant  in  the  uplands  and  pines  replace  the  podocarps.  The 
rain  forest,  rich  in  species  and  with  a  great  diversity  of  palms, 
contains  many  valuable  species  destined  at  some  time  to  be  of 
much  more  commercial  value  than  has  as  yet  been  realized.  The 
northward  extension  of  this  forested  area  along  the  Gulf  coast  of 
Mexico  reaches  to  about  Tuxpan,  and  it  is  practically  identical  in 
character  with  that  of  the  lands  farther  south.  The  climate  is 
hot  and  wet,  the  vegetation  evergreen  and  dense.  The  mangrove 
swamps  of  the  lagoons  are  replaced  inland  by  the  jungle  except 
where  it  has  made  way  for  banana,  cane,  rubber,  mango,  and  other 
cultivated  crops.  This  is  the  center  of  the  vanilla  industry.  Above 
2000  feet  small  oaks  appear,  becoming  more  prominent  with  in- 
creasing altitude  until  at  about  6000  feet  evergreen  oak  forests 
with  a  tropical  undergrowth  are  typical.  At  about  this  elevation 
pines  mingle  with  the  oaks  and  above  7000  feet  the  pines  pre- 
dominate. 


CHAPTER  VII 

The  Sequoias  or  Big  Trees 

"A  living  thing, 

Produced  too  slowly  ever  to  decay, 
Of   form   and   aspect   too   magnificent 
To  be  destroyed." 

— Wordsworth. 

It  is  most  fitting  to  commence  these  sketches  of  tree  ancestors 
with  an  account  of  the  sequoia  which  has  the  most  ancient  Kneage 
of  any  of  the  trees  described  in  the  following  pages.  In  the  days 
when  the  world  was  considered  to  be  only  about  six  thousand  years 
old  and  when  the  few  known  fossils  were  thought  to  be  the  visible 
evidence  of  Noah's  flood,  as  was  first  suggested  by  Martin  Luther, 
it  was  scarcely  remarkable  that  no  one  was  interested  in  tree 
ancestors.  In  fact  there  were  no  such  things  as  ancestors  for  an 
anthropomorphic  deity  had  supplied  them  ready  miade  for  the 
Garden  of  Eden,  and  each  had  produced  according  to  its  kind 
from  that  dehghtful  time  with  only  this  by  no  means  trifhng  and 
wholly  unexplained  exception  that  there  had  been  no  weeds  or 
harmful  trees  until  Adam's  fall  at  wliich  time  all  nature  fell  and 
the  forest  trees  which  formerly  had  all  produced  delightful  fruits 
changed  their  nature  and  now  yielded  worthless  or  poisonous  fruits, 
thistles  and  all  the  hosts  of  agricultural  pests  were  born  and  man 
has  since  been  born  to  trouble  as  the  sparks  fly  upward — the  words 
are  those  of  Job. 

In  modern  days  with  the  passing  of  most  of  the  virgin  forests  of 
the  temperate  zones,  and  the  great  interest  in  preserving  some  of 
our  threatened  trees  such  as  the  sequoia,  black  walnut,  long  leaf 
and  white  pine,  from  total  extermination,  it  is  a  matter  of  surprise 
that  the  thought  that  these  noble  races  of  plants  had  ancestors 
and  a  partly  known  genealogy  is  but  rarely  entertained. 

Tree  genealogies  it  is  true  present  little  of  the  dramatic  as  com- 
pared with  the  wonderful  evolutionary  tree  of  the  elephants,  horses 


40 


TREE    ANCESTORS 


or  camels,  and  yet  most  of  our  familiar  forest  trees  are  of  more 
ancient  lineage,  and  some,  such  as  the  sequoia,  go  back  almost  to 
the  dawn  of  the  tiny  original  progenitors  of  the  warm  blooded 
animals.  Although  the  book  o^f  the  future  is  tightly  sealed  that 
of  the  past  needs  but  understanding  wedded  to  imagination  to  be 
legible,  even  though  its  torn  pages  are  the  rocks  of  the  earth's 
crust.  The  chapters  of  this  great  book  of  history  where  the  records 
of  the  sequoia  occur  are  those  chapters,  pages  upon  pages  of  heaped 
up  shales,  sandstones  and  swamp  deposits,  commencing  with  late 


Fig.  5.  Cone-bearing  Twig  of  the  Big  Tree  of  the  Sierra  NEViUJAS 
(About  f  Natural  Size) 


Jurassic  time  and  continuing  down  the  ages  to  the  present.  The 
entries  of  the  sequoia  ancestry  comprise  innumerable  leafy  twigs, 
many  cones,  fragments  of  wood,  sometimes  seeds,  and  occasionally, 
as  in  Yellowstone  Park  and  at  Florissant,  Colorado,  mighty  silici- 
fied  trunks,  buried  by  tremendous  showers  of  volcanic  ashes  and 
petrified  in  successive  upright  layers  into  forests  of  stone. 

Sequoia  remains  resist  decay  admirably,  pro'bably  because  of 
the  great  amount  of  tannin  that  they  contain,  so  that  their  chances 
of  preservation  as  fossils  in  the  rocks  are  much  better  than  the 


THE    SEQUOIAS   OR   BIG  TREES  41 

average  run  of  plants.  The  cones,  especially,  are  very  common  in 
the  geological  record,  and  one  of  the  common  methods  of  preserva- 
tion is  as  ferruginized  mud  casts,  that  is  the  fine  mud  penetrated 
and  completely  surrounded  the  axis  and  scales  of  the  cone,  the 
chemistry  of  slow  decay  caused  an  impregnation  of  salts  of  iron 
thus  rendering  the  cones  more  resistant  than  the  matrix.  I  have 
collected  such  cones  from  the  Lower  Cretaceous  of  Maryland,  from 
the  Upper  Cretaceous  of  Kansas  and  from  the  early  Tertiary  of 
Dakota.  Such  cones  almost  exactly  like  those  of  the  existing 
redwood  can  be  found  in  abundance  in  the  coulees  of  the  present 
arid  badlands  of  western  Dakota  where  they  have  weathered  out 
of  the  surrounding  rocks  and  where  their  presence  indicates  a  very 
different  environment  and  climate  once  where  now  the  dry  farmer 
faces  often  heart  breaking  failure. 

The  big  trees,  as  both  of  our  sequoias  deserve  to  be  called,  have 
furnished  a  theme  for  song  and  story  and  have  been  a  Mecca  for 
the  tourist  for  so  long  a  time  that  any  remarks  regarding  the  size 
or  longevity  of  the  far  famed  trees  of  Mariposa  and  Calaveras  may 
seem  trite.  Their  present  isolation — for  they  are  but  few  in 
number  and  do  not  seem  to  be  holding  their  own  in  the  struggle 
with  nature  and  the  cupidity  of  civilization — but  adds  to  their 
majestic  grandeur. 

To  the  traveller  who  journeys  to  California  and  for  the  first 
time  stands  in  their  mighty  presence  many  questions  may  suggest 
themselves — the  number  is  the  I.Q.  of  our  civilization.  How  long 
has  it  taken  these  giants  of  the  forest  to  reach  up  some  400  feet 
above  mother  earth?  Were  they  created  thus?  Were  they  just 
entering  upon  a  career  when  the  red-man's  fire  or  the  pale-face's 
ax  checked  them,  or  are  they  the  survivors  of  a  long  existing  line, 
struggling  to  maintain  themselves  in  their  last  mountain  strong- 
hold? 

The  records  of  their  descent  are  locked  up  in  the  rocks  and  clays 
of  the  world,  bits  of  branches,  cones  and  pieces  of  wood  that  floated 
down  to  the  ancient  seas  and  were  entombed  in  the  sand  and  mud, 
to  become  preserved  as  fossils  for  the  edification  of  later  ages. 
Kxploration  has  unearthed  a  part  of  this  record.     Sequoia  remains 


42  TREE    ANXESTORS 

have  been  found  at  almost  every  locality  where  later  Mesozoic 
fossil  plants  have  been  discovered.  This  is  especially  true  of  the 
tiny  cones,  in  fact  the  fossil  cones  of  the  sequoia  were  described 
in  Europe  away  back  in  the  first  quarter  of  the  nineteenth  century, 
before  the  big  trees  of  California  had  been  discovered  or  described. 

The  book  of  life  which  is  the  sedimentary  rocks  teaches  us  that 
death  has  played  sad  havoc  in  their  noble  line  and  almost  entirely 
swept  away  their  principality.  Some  have  been  dead  about  seven 
million  years,  with  thousands  of  feet  of  rock  lying  vertically  over 
their  graves.  Ever3avhere  over  the  broad  land  areas  of  the  North- 
ern Hemisphere  they  are  seen  to  have  been  replaced  by  other  races. 
But  before  turning  to  their  ancestors  let  us  take  a  glance  at  the 
surviving  heirs — the  Kving  trees. 

Their  scientific  name  was  formed  from  Sequoiah,  the  inventor  of 
the  Cherokee  alphabet.  Popularly  they  are  known  as  THE  big 
trees.  There  two  species — the  real  giant.  Sequoia  washingtoniana, 
sometimes  called  Sequoia  gigantea,  and  sometimes  Sequoia  welling- 
tonia,  although  the  first  name  is  the  most  appropriate  for  what 
John  Muir  called  "Nature's  forest  masterpiece;"  and  the  red- 
wood, Sequoia  sempervirens.  Barring  the  technical  features  which 
amply  distinguish  the  two  they  are  superficially  very  similar,  the 
second  seeming  merely  a  slightly  smaller  edition  of  the  first.  Both 
are  evergreen  with  small  leaves  and  small  cones;  columnar  massive 
trunks,  buttressed  below,  and  covered  with  a  great  thickness  of 
reddish  fibrous  bark — that  of  the  redwood  being  a  cinnamon  red 
and  that  of  the  big  tree  somewhat  lighter  in  color.  Both  are  culti- 
vated as  ornamental  trees  in  temperate  countries,  especially  in 
central  and  southern  Europe. 

The  redwood  occasionally  occurs  as  pure  stands  on  protected 
flats  and  terraces  along  streams,  in  sheltered  moist  coastal  plains 
from  southern  Oregon  to  Monterey  County,  Cahfornia,  near  the 
Pacific  coast.  More  often  it  is  found  scattered  among  Douglas 
fir,  tanbark  oak,  and  other  species.  It  is  closely  confined  to  the 
humid  regions  subject  to  frequent  and  heavy  sea  fogs.  Like  its 
elder  brother  it  is  not  at  all  tolerant  of  shade.  The  redwood  pro- 
duces a  normal  number  of  seeds  but  foresters  have  found  that  less 


THE    SEQUOIAS   OR   BIG   TREES  43 

than  a  fourth  of  these  seeds  are  viable  (or  will  sprout  in  other  words). 
It  makes  up  in  a  measure  for  this  lack  of  seed  vitality  by  sprouting 
rapidly  and  abundantly  from  either  old  or  young  stumps,  or  wind 
broken  tops— a  habit  almost  unique  among  conifers.  The  height 
of  large  redwoods  ranges  from  200  to  350  feet  in  exceptional  cases. 
The  average  is  less,  and  the  usual  trunk  diameter  of  large  trees  is 
10  to  15  feet,  although  widths  of  as  much  as  28  feet  have  been 
recorded.  Little  is  known  of  its  longevity.  A  large  tree  whose 
rings  were  counted  by  the  Forest  Service  showed  1373  which  are 
quite  likely  to  represent  annual  rings  in  a  region  of  rainy  winters 
and  dry  summers. 

The  leaves  are  fiat  and  two  ranked  on  the  twigs,  not  unlike  those 
of  the  bald  cyj^ress  of  our  eastern  swamps  but  stiff  er  and  decurrent 
at  their  bases.  The  wood  is  heavier  than  that  of  its  brother  the 
big  tree,  very  soft,  moderately  fine  grained,  exceedingly  brittle, 
and  a  purplish  clear  red-brown  in  color.  It  is  of  great  commercial 
importance  because  of  its  ease  of  working,  its  very  great  durability 
and  the  large  sizes  of  clear  wood  obtainable,  so  that  the  redwood 
no  less  than  its  brother  is  in  great  need  of  ofilicial  protection  to  pre- 
vent its  being  lumbered  entirely  off  of  the  face  of  the  earth,  and 
there  is  a  rising  volume  of  popular  protest  against  its  destruction. 

The  big  tree  is  much  more  limited  in  individuals  and  in  range 
than  the  redwood,  occurring  only  as  scattered  groves  on  the  western 
slopes  of  the  Sierra  Nevadas  from  southern  Placer  to  Tulare  county, 
Cahfornia,  generally  at  elevations  of  from  5000  to  8500  feet  in  the 
Sierra  fog  belt.  The  leaves  are  more  needle-like  and  less  spreading 
than  those  of  the  redwood,  running  round  the  twig  and  not  arranged 
in  two  apparent  rows  on  opposite  sides.  The  cones  are  shghtly 
larger,  but  still  tiny  for  so  great  a  tree.  The  dimensions  of  the 
big  trees  are  popularly  much  overestimated.  Usually,  mature 
trees  average  about  275  to  300  feet  tall  and  with  a  trunk  diameter 
of  about  20  feet.  Occasionally  they  reach  heights  50  to  75  feet 
greater  and  diameters  of  35  feet.  They  are  therefore  normally 
about  75  feet  taller  than  the  average  old  redwood,  and  with  a 
trunk  almost  twice  as  massive.  The  big  tree  produce  abundant 
seed  at  short  intervals  interspersed  with  especially  heavy  seed 


44 


TREE   ANCESTORS 


years.  The  seeds,  unlike  those  of  the  redwood,  possess  great 
vitality,  and  being  small,  slightly  winged  and  formed  high  in  the 
air,  they  are  widely  scattered  by  the  wind  in  the  late  fall  and  early 
winter,  and  grow  rapidly  the  following  season  if  they  happen  to 


Fig.  6.  Cone-bearing  Twig  of  the  JModern  Redwood  (About 

Size) 


Natural 


have  fallen  in  cleared  areas  with  full  light,  where  they  may  reach 
a  height  of  six  feet  in  as  many  years.  It  may  be  noted  that  the 
big  trees  live  in  a  cooler,  drier  habitat  than  does  the  redwood  and 
in  a  temperature  ranging  in  its  extremes  from  — 12°  to  100°  Fahren- 


THE    SEQUOIAS   OR  BIG  TREES  45 

heit,  so  little  that  is  precise  can  be  deduced  with  respect  to  the 
geological  climates  that  fossil  sequoias  indicate. 

The  wood  is  a  brilliant  rose-purple  red  when  first  cut  becoming 
somewhat  duller  later.  It  is  very  light  and  brittle,  coarse  for  the 
first  four  or  five  hundred  years  of  early  more  rapid  growth,  becom- 
ing somewhat  finer  grained  with  age.  It  and  the  bark,  which  is 
enormously  thick,  contain  very  large  amounts  of  tannin,  which 
explains  why  prostrate  trunks  will  He  on  the  ground  for  centuries 
without  decay  affecting  anything  but  the  sapwood,  and  I  have 
already  called  attention  to  this  imperishabihty  as  a  factor  in  fossili- 
zation.  The  wood  is  much  sought  after  by  lumbermen,  passing  in 
the  market  as  "redwood,"  although  Hghter  and  more  brittle.  In 
fact  the  big  tree  wood  is  so  brittle  and  the  tree  so  large  that  when 
it  goes  down  its  enormous  weight  often  almost  completely  de- 
molishes it.  According  to  the  records  of  the  forestry  bureau  in 
no  case  is  more  than  25  to  30  per  cent  of  saw  timber  obtained,  so 
that  lumbering  it  is  not  only  a  crime  against  civilization  but  wanton 
wastefulness. 

Fortunately  some  of  the  groves  are  on  reservations  and  receive 
protection,  but  constant  vigilance  of  patriotic  citizens  is  reguired, 
since  as  recently  as  the  1922  congress,  a  bill  ostensibly  to  bring  more 
areas  of  big  trees  under  government  control  by  changing  the  bound- 
aries of  the  big  tree  park,  has  been  attacked  as  a  gerrymander  to 
make  available  for  lumbering  some  choice  protected  groves  w^hile 
adding  areas  of  no  or  few  trees  to  the  reservation.  This  is  denied, 
however,  and  must  be  viewed  with  due  reservation. 

Huge  as  the  big  trees  are,  their  size  is  less  wonderful  than  their 
longevity.  Under  a  thousand  years  of  age  they  are  youngsters. 
Huntington  counted  the  rings  of  79  that  were  over  two  thousand 
years  old  and  4  that  were  over  three  thousand.  Estimates  of  the 
still  standing  giants  place  the  age  of  some  of  them  at  from  four  to 
five  thousand  years,  but  Sudworth  states  that  it  is  doubtful  if  any  of 
the  standing  trees  are  over  four  thousand  years  old.  The  only  good 
that  has  come  out  of  lumbering  the  big  trees  has  been  the  oppor- 
tunity it  has  given  scientists  of  measuring  the  annual  rings  and 
thus  getting  a  climatic  record  of  local  accuracy  covering  a  two  to 


46  TREE    ANCESTORS 

three  thousand  year  period — the  thickness  of  the  annual  ring  being 
directly  related  to  the  amount  of  precipitation  and  humidity. 

Huntington,  who  has  made  climatic  studies  in  both  hemispheres 
asserts  that  he  can  see  the  cause  of  the  famine  in  the  days  of  Eli- 
jah; the  good  crops  of  Mediterranean  countries  at  the  time  of 
Christ;  the  long  period  of  drought  which  stimulated  the  Arabs, 
unified  by  Mohammedanism,  to  overrun  their  former  limits;  and 
many  other  historic  events  of  the  Old  World,  in  the  climatic  curve 
made  by  measuring  the  sequoia  rings. 

Year  after  year  the  sequoias  have  been  adding  layer  after  layer 
to  their  girth  in  ever  widening  circles.  The  thousands  of  tons  of 
bark  shed  by  each  tree  during  its  long  career;  the  tens  and  hundreds 
of  thousands  of  tons  of  sap  that  have  coursed  through  their  vener- 
able trunks;  and  the  innumerable  progeny  of  a  single  tree  in  the 
older  more  propitious  days — a  contemplation  of  these  questions 
assists  us  in  realizing  the  true  proportions  of  these  forest  monarchs. 
Imagination,  however,  falls  short  in  its  attempt  to  picture  the  ex- 
quisite beauty  of  the  virgin  forest,  standing  age  after  age  in  all  its 
unsullied  glory — a  veritable  forest  primeval. 

Some  of  the  Cahfomia  trees  were  still  in  their  youth  and  others 
were  approaching  middle  age  when  the  various  hordes  of  barbarians 
overran  Europe.  They  had  almost  reached  their  full  growth  at 
the  time  of  the  War  of  the  Roses  and  the  discovery  of  America. 
They  had  reached  their  present  height  and  girth  and  ripe  old  age 
before  modern  science  had  commenced  its  renaissance;  in  fact 
every  avenue  of  human  endeavor^ — social,  rehgious,  industrial  and 
intellectual — has  shown  its  most  marvellous  progress  during  the 
time  that  it  has  taken  the  sequoias  to  add  but  a  few  feet  to  their 
already  giant  frames. 

Turning  now  to  the  ancestral  line  of  the  sequoias  and  to  the 
more  genial  days  of  long  ago  when  they  were  not  restricted  to  a 
small  area  in  a  single  state  but  ranged  over  at  least  four  continents, 
it  may  be  noted  that  the  earliest  positively  identified  sequoia  that 
is  known  was  found  a  few  years  ago  in  the  upper  Jurassic  of  France, 
in  the  deposits  of  which  age  it  is  represented  by  characteristic 
cones.     When  we  say  that  sequoias  flourished  in  the  upper  Jurassic 


THE   SEQUOIAS   OR   BIG   TREES  47 

we  have  a  dim  idea  that  they  must  be  a  pretty  old  type  and  that, 
although  compared  to  the  most  ancient  known  rocks  the  Jurassic 
rocks  are  mere  infants,  still  the  Jurassic  age  came  to  a  close  several 
million  years  ago.  But  we  can  no  more  form  a  concept  of  the  dura- 
tion of  several  million  years  than  we  can  of  astronomical  distances, 
and  it  is  only  by  glancing  at  the  progress  of  life  on  the  globe  during 
all  those  years  that  we  get  any  sort  of  an  idea  of  the  remoteness  of 
the  Jurassic  period. 

Could  imagination  transport  us  to  Jurassic  times  and  set  us  down 
near  the  mouth  of  where  the  Hudson  now  flows,  we  should  find  little 
that  was  familiar  in  either  the  fauna  or  the  flora.  The  sediments 
which  now  exist  as  the  red  sandstones  and  shales  of  the  Connecticut 
valley  and  New  Jersey  had  already  been  deposited.  Volcanic 
activity  had  been  considerable  and  vast  quantities  of  molted  rock 
had  been  forced  through  the  outer  crust  of  the  earth,  forming,  among 
others,  the  Orange  Mountains  of  New  Jersey  and  the  noble  line 
of  Palisades  along  the  Hudson.  However,  it  is  quite  probable 
that  one  would  have  been  as  little  disturbed  by  earthquakes  seven 
or  eight  million  years  ago  than  are  the  inhabitants  of  New  Jersey 
at  the  present  time  by  the  sinking  of  their  eastern  coast.  Events 
moved  with  inconceivable  slowness  then  as  now.  Cur  Jurassic 
sojourner  would  have  found  everything  strange.  In  the  marshes 
flourished  great  ferns  competing  with  an  amazing  variety  of  forms 
known  as  cycads — curious  and  ancient  plants  of  which  the  com- 
monly cultivated  sago  palm  is  a  familiar  example.  In  the  dryer 
areas,  along  with  the  majority  of  the  cycads  there  flouirshed  the 
numerous  ancestors  of  the  ginkgo,  the  maiden-hair  tree,  that  unique 
relic  of  bygone  days,  which  has  been  saved  from  extinction  in 
modern  times  by  the  loving  care  of  the  priests  about  the  temples 
of  China  and  Japan. 

There  were  apparently  no  representatives  of  those  plants  wliich 
are  dominant  in  the  world  today — the  flowering  plants  or  angio- 
sperms  as  they  are  called.  Ancient  lung-fishes,  gar  pikes  and  croco- 
diles haunted  the  rivers.  At  sea  were  swarms  of  sharks  and  ganoid 
fishes.  Bat-like  flying  reptiles  were  the  common  denizens,  no 
true  birds  being  known  from  North  .America  at  this  early   date, 


48  TREE    ANCESTORS 

although  the  lizard  tailed  bird  or  Archaeopteryx  the  missing  Knk 
between  birds  and  reptiles  haunted  the  reefs  of  Solnhofen  in  Bavaria 
at  this  time.  Somewhat  later  we  fmd  the  curious  toothed  birds 
of  western  North  America.  Sea-inhabiting  reptiles  of  gigantic 
size,  long  necked,  sea  serpent-like  plesiosaurs  and  dolphin-like 
ichthyosaurs,  land  inhabiting  dinosaurs  (the  name  means  terrible 
lizard)  of  immense  size  and  bizarre  form  were  the  dominant  crea- 
tures, while  the  noble  class  of  mammals  with  man  at  their  summit 
was  still  but  a  promise  and,  so  far  as  the  fossils  indicate,  represented 
by  only  a  few  forms  of  mouse-like  size.  The  continents  had  not 
yet  assumed  their  modern  forms.  Such  great  mountain  chains 
as  the  Andes,  Alps,  Himalayas  and  Rockies  had  not  been  elevated ; 
and  yet  the  sequoia  flourished  and  its  cones  then  were  not  very 
different  from  those  grown  in  California  at  the  present  time. 

The  next  succeeding  geological  period,  the  Cretaceous,  continued 
to  be  the  age  of  gigantic  reptiles.  Occasional  bones  and  teeth  of 
these  and  other  related  creatures  are  found  in  the  marl  beds  that 
were  deposited  in  the  shallow  seas  along  the  eastern  coast  of  those 
days,  and  still  more  are  found  in  the  chalky  deposits  of  the  Creta- 
ceous sea  which  then  covered  our  great  plains  country.  The  Mis- 
sissippi valley  was  a  part  of  a  great  gulf  that  extended  northward 
from  the  present  Gulf  of  Mexico  almost  to  the  Arctic  Circle,  and 
which  was  a  veritable  summer  sea,  peopled  with  gigantic  sea-liz- 
ards, mosasaurs,  and  with  a  host  of  strange  forms.  Flying  reptiles 
with  a  spread  of  fifteen  to  twenty  feet  circled  overhead. 

The  vegetation,  however,  particularly  during  Upper  Cretaceous 
times  began  to  assume  a  more  modern  aspect  and  we  find  along 
with  ancient  types  of  ferns,  broad  leafed  conifers  and  juniper-like 
evergreens,  numerous  leaves  of  willows,  figs,  magnohas  and  sassa- 
fras. The  earhest  known  palms  as  well  as  the  first  leaves  of  many 
of  our  modern  hardwoods  date  from  this  time.  The  Cretaceous 
clays  that  skirt  Raritan  Bay  in  New  Jersey  aboimd  with  these 
layers  of  leaves,  as  do  also  the  Dakota  sandstone  of  the  middle 
west.  The  fine  sequoia  with  the  large  cone  and  needle-like  curved 
leaves  figured  is  from  clays  near  Cliffwood,  New  Jersey,  where  the 
twugs  are  among  the  most  abundant  fossils,  looking  like  elegant 


THE   SEQUOIAS   OR   BIG   TREES  49 

lithographs  against  the  background  of  dove-colored  clay.  This 
species,  which  is  known  as  Sequoia  Reichenhachi,  had  cones  almost 
exactly  like  those  of  the  living  Cahforhia  big  tree,  and  the  foliage 
was  somewhat  similar.  It  was  a  very  wideranging  form  both  in 
this  country  and  Europe,  and  is  considered  to  have  been  the  source, 
in  part  at  least,  of  the  amber  which  is  so  common  in  the  Cretaceous 
of  the  Atlantic  Coastal  Plain, 

A  number  of  other  fossil  species  of  sequoia  show  an  equally  wide 
range.  One  of  these  has  an  appearance  so  much  like  its  descendent 
the  existing  redwood  that  I  have  not  figured  the  fossil,  which  is 


Fig.  7.  Cone-bearing  Twig  of  a  Widespread  Cretaceous    Big  Tree, 
Sequoia  REiciiENBAcm  (About  §  Natural  Size) 

known  as  Sequoia  Langsdorfii.  Its  leafy  two-ranked  twigs  and 
small  cones  have  been  found  almost  everywhere  throughout  the 
Northern  Hemisphere  where  plants  beds  occur,  and  it  ranges  pretty 
well  through  Tertiary  time,  its  range,  both  chronologically  and 
geographically  being  greater  than  that  of  any  other  known  sequoia. 
Another  very  abundant  Tertiary  form,  also  widely  spread  is  Sequoia 
CouUsii,  which  is  shown  in  the  accompanying  illustration.  It  is 
of  especial  interest  because  of  its  pecuhar  foliage,  and  also  from 
the  fact  that  only  recently  has  it  been  definitely  proved  to  be  a 
true  sequoia  in  the  face  of  considerable  botanical  differences  of 
opinion. 


50 


TREE    ANCESTORS 


During  the  three  to  five  million  years  of  Cretaceous  time  the 
sequoias  had  flourished  and  become  widespread.  They  saw  many 
changes  taking  place  in  the  world  about  them.  Beneath  their 
shade  new  races  were  springing  up;  the  plants  of  a  modern  type 
which  were  destined  to  replace  all  others  in  the  struggle  for  exist- 
ence had  obtained    their  start;    animals    gamboled  about  their 


Fig.  8.  Cone-bearing  Branch  of  a  Common  JNIiocene  Big  Tree,  Sequoia 
CouTSii  (About  §  Natur.^l  Size) 


trunks  or  climbed  in  their  branches  that  were  destined  to  replace 
the  unintelligent  and  clumsy  reptiles  and  bye  and  bye  to  give  rise 
to  the  horses,  dogs  and  cats  of  a  later  day,  and  finally  to  produce 
that  animal  which  was  to  attain  universal  disoribution,  and  to  be 
the  destroyer  of  countless  other  species — man. 


THE    SEQUOIAS   OR   BIG   TREES  51 

Remains  of  sequoias  from  the  lower  beds  of  the  Cretaceous  have 
been  found  in  western  Europe,  in  Spitzbergen,  in  Texas  and  in  the 
eastern  United  States.  In  sUghtly  more  recent  deposits  we  find 
them  in  Greenland,  Canada,  in  the  Black  Hills  and  in  Montana. 
By  the  middle  of  the  Cretaceous  we  find  over  a  dozen  different 
species  spread  over  the  United  States,  with  still  others  in  Greenland 
and  in  central  and  western  Europe.  Their  remains  are  often 
extremely  common,  whole  branches  bearing  numerous  cones,  and 
innumerable  twigs,  often  beautifully  preserved,  being  common 
fossils.  The  warm  humid  climate  of  the  period  seems  to  have  been 
very  favorable  for  their  development,  and  the  elevation  of  the 
land,  by  which  natural  bridges,  such  as  those  closing  Bering  Straits 
and  the  English  Channel,  enabled  them  to  spread  all  over  the  north- 
ern hemisphere  and  even  into  the  southern,  for  in  the  next  age, 
the  Eocene,  we  find  their  remains  in  far-off  Australia  and  New 
Zealand,^  while  others  occur  in  Alaska,  stragglers  from  the  migra- 
tion into  Asia. 

The  great  frozen  north  of  today  had  not  yet  been  hinted  at,  a 
warm  climate  prevailed  even  in  the  far  north,  and  Greenland  was 
the  garden  spot  that  its  name  implies.  On  its  western  coast  many 
plant-beds  have  been  discovered,  containing  the  remains  of  tree- 
ferns,  cycads,  incense  cedars,  figs,  camphor  trees,  magnolias,  and 
other  natives  of  warmer  climes.  This  northern  region  with  numer- 
ous land  connections  to  lower  latitudes  was  probably  the  original 
home  of  our  modern  floras  and  faunas,  which  spread  southward  in 
successive  waves  of  migration.  We  know  that  the  Mid-Cretaceous 
witnessed  the  apparently  sudden  appearance  of  a  host  of  new  and 
higher  types,  and  the  basal  Eocene  witnessed  a  Hke  sudden  appear- 
ance of  mammalian  types  and  a  second  and  more  profound  modern- 
ization of  the  floras.  It  is  in  the  frozen  North  or  the  unexplored 
heart  of  Asia  that  we  look  today,  hopeful  that  in  one  or  the  other  of 
those  strategic  regions  that  we  will  find  the  fossfls  that  will  shed 
their  light  on  our  problems  of  descent  and  distribution. 

^  The  identification  of  these  antipodean  remains  is  not  entirely  beyond 
question. 


52  TREE    ANCESTORS 

With  Lhe  ushering  in  of  the  Eocene  period  the  gigantic  reptiles 
are  entirely  replaced  by  higher  types;  small  mammals,  some  races 
of  which  soon  attained  great  size,  uncouth  beasts  long  since  passed 
away,  besides  the  remote  and  generalized  ancestors  of  some  of 
our  modern  animals.  It  is  in  the  rocks  of  this  period  that  we  find 
the  dainty  little  four-toed  ancestor  of  the  horse.  The  Eocene, 
together  with  the  next  period,  the  OHgocene,  represent  a  couple  of 
milHon  years,  during  which  the  sequoias  were  almost  as  abundant 
and  widespread  as  are  the  pines  in  our  existing  flora.  In  the  far 
west  this  was  a  time  of  plains,  rivers,  and  lakes,  suggesting  the 
Louisiana  country  of  the  present.  Sequoia  cones  almost  identical 
with  those  of  the  existing  redwood  are  sometimes  excessively 
abundant  where  now  the  country  is  semi-arid  and  practically 
treeless. 

Along  with  the  sequoias  were  many  hardwood  trees — oaks  and 
maples,  hickory  and  ash ;  alligators  pushed  their  way  through  the 
sedges;  the  cypress  and  palmetto  grew  in  Colorado,  Montana,  and 
British  Columbia.  Stately  palms  furnished  shade  for  primitive 
rhinoceroses,  tapirs  and  camels;  around  the  water  courses  grew 
swamp  maples  and  alders,  gum  trees  and  mulberries;  figs  still 
flourished  in  the  latitude  of  Puget  Sound.  Monkeys  swung  from 
branch  to  branch  and  gathered  fruits,  where  today  there  is  nothing 
but  the  barren  wastes  of  the  alkali  "bad-lands." 

The  next  period,  the  Miocene,  withessed  the  zenith  of  sequoia 
development.  Contemporaneous  with  the  tapirs,  rhinoceroses, 
horses,  the  trees  ranged  farther  than  their  active  associates  and 
are  found  from  Tasmania  (?)  to  Spitzbergen,  and  from  Ireland 
to  Japan.  Their  remains  are  everywhere — in  France,  Italy, 
Greece,  America — they  had  even  found  their  way  across  the  equator 
and  down  along  the  South  American  coast  as  far  as  Chile. 

In  the  Yellowstone  region  whole  forests  have  been  changed  to 
stone  by  the  mineral  waters,  or  buried  in  the  showers  of  ashes  from 
the  active  volcanoes  in  the  vicinity.  The  remains  of  the  trunks 
are  still  from  6  to  10  feet  in  diameter,  and  the  erect  butts  are  often 
30  feet  or  more  in  height,  standing  just  as  they  grew,  a  veritable 
Aladdin's  forest  turned  to  stone.     From  a  microscopic  study  of  the 


THE    SEQUOIAS   OR   BIG   TREES  53 

wood  we  find  that  these  Yellowstone  trees  are  scarcely  to  be  dis- 
tinguished from  the  Californian  redwood  and  it  seems  a  reasonable 
inference  that  they  represent  its  direct  ancestor,  particularly  as 
other  petrified  woods  from  western  Canada  are  likewise  closely 
related  to  the  redwood.  The  Miocene,  like  the  Eocene  and  OHgo- 
cene  periods,  was  characterized  to  a  large  exent  by  vast  continental 
deposits  laid  down  chiefly  by  streams,  small  lakes  and  wind  action. 
To  the  westward  the  Rocky  mountains  were  rising  and  bringing 
about  the  development  of  the  great  plains  type  of  country. 

The  volcanic  eruptions,  which  first  became  a  prominent  feature 
during  the  Cretaceous,  culminated  during  the  Miocene,  as  the 
immense  number  of  extinct  cones  in  the  western  half  of  North 
America  give  abundant  evidence.  The  interval  between  the  close 
of  the  Miocene  and  the  modem  sequoias  is  imperfectly  known. 
CHmates  were  becoming  cooler  and  the  sequoias  were  on  the  wane, 
although  they  are  not  at  all  uncommon  even  at  this  late  time  in 
Germany  and  Holland.  But  few  fossils  are  found  and  it  is  presumed 
that  the  elevation  of  mountain  ranges  shutting  off  the  vernal  breezes 
and  the  consequent  alterations  in  humidity,  as  well  as  the  vast  changes 
attendant  upon  the  coming  of  the  ice  fields  of  the  glacial  period, 
were  sufficient  to  all  but  extinguished  the  noble  sequoia  family. 

At  about  the  time  the  Neanderthal  skull  housed  the  brain  of  a 
cave  dweller  who  fashioned  the  paleolithic  flints,  and  who  dwelt 
in  the  fear  of  the  great  hairy  mammoth,  the  cave  bear,  the  hyaena 
and  the  wooly  rhinoceros,  or  shortly  thereafter,  the  present  sequoias 
reached  their  habitation  in  California.  Could  they  but  hand  down 
to  us  the  record  of  history  embraced  in  a  generation  or  two,  each 
lasting  between  two  and  four  thousand  years,  what  a  tale  they 
might  unfold.  Tradition  has  it  that  Napoleon  encouraged  his 
soldiers  before  the  battle  of  the  pyramids  with  the  picturesque 
phrase  'forty  centuries  look  down  upon  you,'  and  yet  the  span  of 
a  single  sequoia  about  equals  what  to  the  biblical  chronologies  of 
Napoleon  seemed  the  limit  of  time.  Many  of  the  still  vigorous 
and  growing  trees  sprouted  about  the  time  that  Christ  was  born 
at  Bethlehem  in  Judea.  Most  of  those  still  standing  had  com- 
menced to  grow  at  least  before  the  fall  of  Rome.     We  can  count 


54 


TREE    ANCESTORS 


the  annual  layers  in  the  wood  of  those  which  have  been  cut  down, 
and  calculate  with  considerable  accuracy  their  age  and  the  varying 
rapidity  of  their  growth.  For  instance,  the  huge  section  on  exhibi- 
tion at  the  American  Museum  of  Natural  History  shows  that  the 
climate  of  California  was  very  propitious  about  the  time  that 
Charlemagne  was  crowned  by  Pope  Leo  on  Christmas  day,  A.D. 


Fig.  9.  Sketch  Map  Showing  Present  Range  (solid  black)  and  Past 

Distribution  of  the  Sequoias  (lined  areas)  and  Their  Probable 

Paths  of  Migration 

800,  as  is  evinced  by  the  rapid  growth  of  the  tree  at  that  time  shown 
by  the  comparatively  thick  layer  it  added  to  its  girth. 

We  can  but  wonder  at  the  persistence  of  this  type  practically 
unchanged,  for  eon  after  eon,  while  all  around  were  dissolution 
and  evolution.  Their  early  contemporaries  are  almost  without 
exception  cut  off,  and  were  we  to  go  still  further  back  to  the  prob- 
able ancestors  of  the  sequoias,  the  Voltzias  of  the  earlier  ages,  we 


THE    SEQUOIAS   OR    BIG   TREES  55 

could  carry  the  genealogy  back  several  million  more  years,  almost 
to  the  coal  period. 

And  yet  the  vicissitudes  of  time  have  not  succeeded  in  wholly 
obhterating  these  ancient  records  preserved  in  the  great  book  of 
history  whose  torn  pages  are  the  sohd  rock,  and  we  are  able  to 
decipher  a  line  here  and  a  broken  chapter  there,  gradually  piecing 
together  the  main  facts  of  the  story,  the  reading  of  which  becomes 
not  only  a  labor  of  love,  but  a  task  of  the  most  absorbing  interest. 

That  we  do  not  treasure  the  sequoias  or  any  of  our  forest  trees 
sufficiently  is  a  reflection  upon  our  democracy.  I  sometimes  wish 
we  moderns  were  less  pragmatic  and  that  our  bump  of  reverence 
was  less  vestigial  for  then  not  only  the  redwoods  but  all  of  our  trees 
might  become  as  sacred  as  they  deserve  to  be  and  even  a  lumber 
trust  might  hesitate  to  turn  these  abodes  of  the  gods  into  waste 
places.  Our  forests  hke  the  stars  or  the  changing  season  are  won- 
ders whose  lessons  and  value  have  become  dimmed  because  of  long 
familiarity.  If  we  saw  them  but  once  or  twice  in  a  hfetime  they 
would  be  treasured  accordingly.  One  has  but  to  dwell  in  a  tree- 
less desert  for  months  to  have  awakened  such  a  love  for  the  forests 
as  will  last  forever. 

The  accomanying  map  of  the  world  shows  the  tiny  black  area  on 
our  Pacific  coast  where  the  sequoia  has  hngered  into  modern  times, 
the  lined  area  the  region  over  which  it  spread  during  its  past  history, 
and  the  arrows  indicate  the  probable  directions  of  radiation. 


CHAPTER  Vni 

The  Bald  Cypress 

Lumberman  spare  the  forest — the  glory  of  days  long  past,  the  primeval  home 
of  the  race. 

There  are  a  considerable  number  of  plants  and  animals  that  well 
deserve  to  be  called  Hving  fossils  because  their  living  representatives 
are  the  last  of  a  very  long  line  that  flourished  over  milHons  of 
years  of  earth  history  during  which  they  were  more  abundant  and 
varied  than  they  are  today.  The  cycads  are  such  living  fossils 
their  ancestry  going  back  to  the  far  off  days  of  the  Coal  Measures, 
as  does  also  the  ginkgo  or  maidenhair  tree  of  our  parks,  the  latter, 
a  once  cosmopolitan  type,  now  existing  as  a  single  species  whose 
native  home  is  eastern  Asia. 

It  may  almost  be  considered  axiomatic  in  tree  studies  that  when 
a  particular  type  is  represented  in  the  modem  flora  by  a  very  few 
species  of  restricted  and  disconnected  range,  like  the  magnolia, 
tulip-tree  or  sassafras,  and  many  others  might  be  mentioned,  such  a 
type  will  be  found  to  have  had  a  long  and  most  interesting  geologic 
history,  and  we  can  often  make  such  a  prediction  of  a  tree  species 
even  if  we  have  not  been  fortunate  enough  to  discover  the  fossil 
reHcs  of  its  ancestral  forms. 

The  bald  cypress  is  a  striking  illustration  of  this  principle.  Its 
botanical  name,  Taxodium,  was  bestowed  in  the  first  instance 
because  of  its  resemblance  to  the  old  world  yew  (Taxus),^ although 
the  former  is  a  much  more  imposing  and  graceful  tree  and  alto- 
gether lacks  the  funerial  aspect  of  the  yew.  It  is  a  close  relative 
of  the  sequoia  and  the  cypress  and  sequoia  have  come  down  the 
ages,  very  often  in  intimate  association. 

The  bald  cypress  of  today  is  a  large  tree  with  a  tall  columnar 
tapering  trunk  and  a  pyramidal  form  which  becomes  round  crowned 

^  The  genus  Taxus  is  not  confined  to  the  Old  World,  but  the  species  familiar 
to  Anglo  Saxons  whose  foliage  the  cypress  was  considered  to  resemble  is. 

56 


THE   BALD   CYPRESS  57 

in  old  age.  Botanists  generally  recognize  three  species — our 
common  bald  cypress  which  ranges  from  the  Coastal  Plain  of 
southern  Delaware  and  Maryland  to  the  tip  of  the  Florida  penin- 
sula, and  westward  along  the  Gulf  Coastal  Plain  to  Texas,  extend- 
ing up  the  Mississippi  and  its  tributary  bottoms  to  those  of  the 
lower  Wabash  River.  Concerning  its  appearance  I  can  do  no 
better  than  quote  the  quaint  remarks  of  William  Bartram,  the 
pre-Revolutionary  traveller,  who  speaks  of  it  as  "in  the  first  order 
of  North  American  trees.  Its  majestic  stature  is  surprising.  On 
approaching  it  we  are  struck  with  a  kind  of  awe  at  beholding  the 

stateKness  of  its  trunk The  delicacy  of  its  color  and  the 

texture  of  its  leaves  exceed  everything  in  vegetation.  .... 
Prodigious  buttresses  branch  from  the  trunk  on  every  side,  each 
of  which  terminates  underground  in  a  very  large,  strong,  serpentine 
root,  which  strikes  off  and  branches  every  way  just  under  the  sur- 
face of  the  earth,  and  from  these  roots  grow  woody  cones,  called 
cypress  knees,  4,  5  and  6  feet  high,  and  from  6  to  18  inches  and  2 
feet  in  diameter  at  the  base." 

This  basally  expanded  butt,  the  horizontal  root  system  with 
the  upright  pointed  knees  which  project  into  the  air  from  the  shal- 
low roots  when  the  tree  is  growing  in  its  natural  habitat  in  wet 
soil,  have  served  to  impart  to  the  tree  a  weirdness,  enhanced  by 
the  swampy  habitat  and  often  by  a  shroud  of  Spanish  moss,  that 
would  have  amply  justified  a  Druidical  or  similar  cult  had 
this  part  of  North  America  been  inhabited  by  aborigines  who  had 
progressed  beyond  the  stone  age  of  culture.  There  is  considerable 
romance  and  folk  song  associated  with  the  bald  cypress  in  our 
South,  particularly  in  the  negro  South. 

One  of  the  characteristics  of  the  bald  cypress  that  impresses  the 
observer  is  its  vitality  despite  the  fact  that  it  is  the  last  representa- 
tive of  its  race  and  one  whose  area  of  distribution  seems  to  be 
slowly  shrinking.  Latrobe  noticed  this  vitahty  in  the  buried  trees 
in  his  description  of  the  Cape  Henry  (Virginia)  sand  dunes  in  1799. 
Similar  instances  may  still  be  seen  in  the  same  region,  and  the 
nearby  patriarchal  cypress  group  of  Lake  Drummond  in  the  Dis- 
mal Swamp  tell  the  same  story.     The  few  that  remain  in  the 


58  TREE    ANCESTORS 

Lake  are  survivors  from  a  bygone  day  when  the  water  level  was 
lower,  and  although  they  are  for  the  most  part  much  wasted  and 
reduced  to  hollow  shells,  they  bravely  put  forth  their  leafy  twigs 
each  season.  I  have  noticed  comparable  instances  along  some  of 
our  southern  rivers  where  small  C3^ress  trees  that  had  been  under- 
mined and  carried  down  stream  by  floods  had  been  able  to  partially 
right  themselves  in  the  subsiding  waters  by  means  of  their  heavy 
expanded  butts  and  which  were  occupying,  apparently  not  greatly 
harmed,  as  involuntary  squatters,  the  narrow  shingle  of  the  river 
sand  bar. 

The  bald  cypress,  Taxodimn  distichum,  in  allusion  to  the  distich- 
ous or  two-ranked  arrangement  of  the  leaves  on  the  twigs,  fre- 
quently reaches  a  height  of  150  feet,  and  usually  has  a  trunk 
diameter  of  4  to  5  feet  and  may  reach  as  much  as  12  feet,  measured 
above  the  expanded  buttresses  and  often  hollow  base.  It  is  much 
sought  by  lumbermen  but  its  swampy  habitat  protects  it  to  some 
extent  from  the  wholesale  destruction  that  is  visited  upon  some  of 
our  hardwoods.  The  excellence  of  cypress  wood  is  proverbial, 
well  meriting  its  reputation,  now  much  advertised  as  "the  wood 
eternal." 

Our  second  native  species,  not  recognized  as  distinct  by  many 
botanists,  is  the  pond  cypress,  or  Taxodimn  imhricarium,  in  allu- 
sion to  the  somewhat  imbricated,  or  at  least,  appressed  habit  of 
the  leaves.  It  is  a  smaller  and  much  less  important  a  tree  with 
less  flat  and  more  appressed  leaves  and  enormously  expanded  butts, 
and  frequents  ponds  rather  than  river  bottoms — the  favorite  abode 
of  its  more  noble  relative. 

The  third  existing  species  is  the  Mexican  cypress  or  Taxodium 
miicronatiim,  Taxodium  monkzumae  or  Taxodium  mexicanum  as 
it  has  been  christened  by  different  authorities.  It  does  not  occur 
within  the  limits  of  the  United  States,  but  is  now  confined  to  scat- 
tered localities  on  the  Mexican  Plateau,  especially  toward  its 
southern  end.  It  seems  probable  that  the  Mexican  cypress  is  a 
close  relative  of  our  familiar  species  which,  in  prehistoric  times, 
perhaps  urged  by  the  Pleistocene  glaciation  of  the  North  country, 
invaded  Central  America,  the  continuity  of  its  range  having  been 


THE   BALD   CYPRESS  59 

subsequently  broken  by  the  progressive  aridity  of  the  great  belt 
of  dry  country  of  northern  Mexico  and  our  border  States. 

Among  these  Mexican  trees  there  are  a  number  of  extraordinary 
size  that  have  attracted  the  attention  of  all  travelers.  Among 
these  is  the  cypress  of  AtHxco  described  by  Humboldt,  the  cypress 
of  Montezuma  at  Chapultepec  which  was  a  notable  tree  four  cen- 
turies ago.  Another  cypress  in  the  village  of  Popatela  near  Mexico 
City,  is  noted  for  its  association  with  Cortez  at  the  time  of  his 
reverses  during  the  Conquest,  and  is  picturesquely  named  Arbol 
de  la  Noclie  Triste. 

The  most  famous  of  these  Mexican  cypress,  the  largest  one  known, 
and  perhaps  the  oldest  living  tree  in  the  world  is  the  great  cypress 
of  Santa  Maria  del  Tule  in  the  village  of  that  name  near  the  capital 
of  the  State  of  Oaxaca  in  southern  Mexico.  This  remarkable  tree^ 
a  photograph  of  which  serves  as  a  frontispiece  of  the  present  work^ 
was  described  by  Humboldt  in  1803,  who  affixed  a  plate  in  one  side 
12  feet  from  the  base,  and  now  nearly  entirely  grown  over.  There 
have  been  a  number  of  measurements  of  this  famous  tree  in  addi- 
tion to  those  of  Humboldt.  Probably  the  most  accurate  are  those 
made  by  von  Schrenk,  to  whom  I  am  indebted  for  the  accompany- 
ing photograph,  and  who  visited  Santa  Maria  del  Tule  just  one 
hundred  years  after  Humboldt's  visit.  The  diameter  of  the  trunk 
of  this  old  giant  above  the  swollen  and  buttressed  base  was  slightly 
over  41  feet,  and  the  estimated  age  of  the  tree  has  been  placed  as 
between  four  thousand  and  six  thousand  years. 

It  is  held  in  great  veneration  throughout  the  country-side  as  it 
should  be,  and  seems  to  be  perfectly  vigorous  and  healthy  notwith- 
standing its  great  age.  It  is  hard  to  picture  an  organism  that  has 
been  growing  since  before  the  flowering  of  Greek  civilization  and 
perhaps  antedating  the  first  dynasty  of  Egypt.  A  tree  associated 
with  the  Maya  culture,  which  has  come  and  gone,  with  the  empire 
of  the  Aztecs,  with  the  coming  of  the  Conquistadores,  the  Colonial 
period,  and,  I  was  about  to  add,  the  Petroleum  period.  If  ever 
misfortune  overtakes  this  patriarch  among  trees  it  is  to  be  hoped 
that  some  scientist  will  happen  along  and  measure  its  growth 
rings,  for  they  would  shed  much  light  on  the  climatic  fluctuations 


60  TREE    ANCESTORS 

of  the  last  few  thousands  of  years.  The  wood  of  this  IMexican 
species  is  soft  and  relatively  weak  and  not  to  be  compared  mth 
that  of  our  commercial  species,  which  is  perhaps  fortunate  or 
some  vandal  would  ere  now,  probably  have  sacrificed  these  memo- 
rials of  the  past  as  so  many  of  our  sequoias  have  been  sacrificed. 

The  cypress  line  is  a  very  ancient  one,  in  fact  the  family  to  which 
it  belongs,  known  as  the  Taxodiaceae,  is  characterized  throughout 
by  an  ancient  lineage,  a  peculiar  modern  distribution,  and  the 
isolation  of  its  various  members.  Most  of  them  have  many  ex- 
tinct species  and  there  are  several  totally  extinct  genera.  Only 
two  of  the  genera  have  as  many  as  three  existing  species  (Taxo- 
dium  and  Athrotaxis) ;  three  of  the  genera  have  but  two  existing 
species  (Sequoia  and  Glyptostrobus) ;  and  four  have  but  a  single 
existing  species  (Sciadopitys,  Cunninghamia,  Taiwania  and  Cryp- 
tomeria).  Their  present  distribution  is  also  an  indication  of  former 
greatness.  Thus  Glyptostrobus  is  Chinese  though  once  cosmopoli- 
tan; Sciadopitys  is  Japanese;  Taiwania  is  confined  to  the  Island  of 
Formosa;  Cunninghamia  and  Cryptomeria  are  Chino-Japanese 
although  the  former  was  once  a  member  of  the  North  American 
flora;  Athrotaxis  is  Australian  although  formerly  found  in  many 
parts  of  the  world;  Sequoia  is  making  its  last  stand  on  our  Pacific 
coast;  and  Taxodium  is  confined  to  the  South  Atlantic  and  Gulf 
border  region.  The  family  is  totally  unrepresented  in  South 
America,  Africa  and  Europe  at  the  present  time,  although  common 
enough  in  Europe  as  recently  as  the  time  immediately  preceding 
the  Ice  Age. 

There  are  no  certainly  identified  records  of  ancestral  bald  cypress 
in  the  Cretaceous  period,  although  it  is  quite  possible  that  some  of 
the  similar  appearing  twigs  of  fossil  conifers  that  have  been  re- 
ferred to  Sequoia  may  really  be  those  of  an  early  cypress.  In  the 
absence  of  preserved  cones  it  would  be  impossible  to  decide  such 
a  question  of  relationship.  The  cypress  is  therefore  less  ancient 
than  Sequoia,  Sciadopitys,  Athrotaxis,  Cryptomeria  and  Glypto- 
strobus, some  of  which  appear  to  have  appeared  in  the  geological 
record  before  the  close  of  the  Jurassic  period. 


THE   BALD    CYPRESS  61 

In  the  earliest  Tertiary,  however,  in  the  days  when  the  primitive 
mammals  were  replacing  the  last  of  the  dinosaurs,  we  find  the  cy- 
press in  many  countries,  and  it  soon  comes  to  be  cosmopolitan  in 
so  far  as  the  Northern  Hemisphere  is  concerned,  although  it  has 
never  been  definitely  recognized  in  the  Sohithem  Hemisphere. 
These  Eocene  records  are  very  numerous  and  are  based  upon  the 
remains  of  leafy  twigs,  seemingly  thus  early  to  have  acquired  the 
deciduous  habit  fqr  which  the  bald  cjrpress  is  notable,  and  which  is 
rather  unique  among  conifers  and  only  shared  by  the  larch  among 
modern  forms,  in  which  however  it  is  the  leaves  and  not  the  twigs 
which  are  shed. 

This  deciduous  habit  may  perhaps  mean  that  the  original  home 
of  the  cypress  was  in  the  far  North,  possibly  during  Cretaceous 
times.  In  addition  to  the  twigs,  cone  scales  and  seeds  are  fre- 
quently found  in  the  rocks,  and  sometimes  wood  showing  the 
anatomy  of  the  genus  is  preserved  although  anatomy  alone  is 
applied  with  difficulty  in  the  differentiation  of  some  of  these  genera. 

The  Eocene  range  of  the  cypress  is  probably  more  remarkable 
than  anything  in  its  later  history,  for  the  Eocene  records  include 
Alaska,  Alberta,  British  Columbia,  Siberia,  Manchuria,  Green- 
land and  Spitzbergen.  From  these  relatively  high  latitudes  the 
cypress  seems  to  have  spread  southward  over  Canada  to  Montana, 
Wyoming  and  Nevada,  and  to  the  shores  of  the  Mississippi  Gulf 
of  that  time.  Presumably  it  also  spread  over  Asia  at  the  same 
time  even  though  we  lack  the  actual  records,  for  it  appeared  in 
Europe  shortly  afterward,  or  with  the  dawn  of  Oligocene  time. 

Unfortunately  we  know  of  but  few  plant  beds  in  North  America 
of  Oligocene  age,  although  we  have  no  reason  for  doubting  the 
continued  presence  of  the  cypress  over  a  large  part  of  North  America 
at  that  time.  In  Europe  there  are  a  number  of  OHgocene  records 
and  these  include  southern  France  and  the  countries  bordering 
the  Baltic  Sea.  The  maximum  of  development  and  range  of  the 
Cypress  was  attained  during  the  next  geological  age — the  Miocene. 
At  that  time  its  remains  are  found  from  Japan  on  the  East  to 
Austria,  Switzerland  and  Italy  on  the  West.  Along  with  the  still 
more  abundant  sequoia,  the  cyi)ress  was  one  of  the  contributors 


62 


TREE   ANCESTORS 


to  the  swamp  deposits  that  formed  the  brown  coal  so  extensively 
present  and  utilized  in  Europe,  and  especially  in  Germany. 

In  North  America  Miocene  cypresses  are  found  in  Virginia  on 
the  east  coast  and  in  Oregon  on  the  west  coast.  In  Virginia  the 
Miocene  cypress  with  leaves,  cones  and  seeds  like  those  of  the 
modem  species  flourished  in  the  swamps  of  the  low  coastal  country. 
Streams  were  sluggish  and  erosion  slight  and  consequently  great 


Fig.  10.  Sketch  Map  Showing  Present  (soled  black)  and  Past 
(lined  areas)  Distribution  of  the  Bald  Cypress 


beds  of  diatoms — tiny  marine  plants  with  siHceous  tests,  accumu- 
lated in  the  shallow  waters  along  those  low  coasts.  The  cypress 
has  never  been  found  in  the  Southern  Hemisphere  and  apparently 
did  not  succeed  in  penetrating  into  South  America  as  did  the  se- 
quoia which  is  found  in  the  lower  Miocene  as  far  south  as  southern 
Chile. 


THE   BALD   CYPRESS  63 

During  the  late  Tertiary  time  which  succeeded  the  Miocene, 
termed  Pliocene  by  geologists,  North  America  again  furnishes  us 
with  but  few  plant  beds.  The  available  deposits  of  this  age  on 
this  continent  are  marine  shell  marls  without  plant  fossils  or  interior 
basin  deposits  with  vertebrate  fossils  in  regions  of  increasing  aridity 
like  the  western  plains  or  mountain  basins,  apparently  too  dry  for 
the  cypress.  Along  our  Gulf  coast  in  what  is  known  as  the  Plio- 
cene Citronelle  formation,  a  series  of  sands  and  muds,  deposited 
in  lagoons  along  the  sea  coast,  there  occur  abundant  remains  of 
twigs,  cone  scales  and  seeds  of  a  cypress  indistinguishable  from 
our  existing  bald  cypress. 

In  Pliocene  Europe  on  the  other  hand,  there  are  preserved  many 
plant  beds  of  this  age  and  the  cypress  was  apparently  one  of  the 
most  common  denizens  of  the  shores  of  the  greatly  expanded  Medi- 
terranean Sea,  which  at  that  time  spread  over  southern  Europe  and 
eastward  into  Asia.  The  accompanying  sketch  map  of  the  world 
shows  graphically  the  areas  occupied  by  the  existing  cypress  (in 
soHd  black)  and  the  approximate  area  over  which  it  extended  its 
range  during  Tertiary  times  (lined  areas). 

At  the  close  of  the  Tertiary  the  long  period  of  more  or  less  wide- 
spread equable  climates  was  broken  by  those  climatic  changes 
which  inaugurated  the  extensive  glaciation  of  the  Pleistocene.  Our 
records  of  Pleistocene  plant  migrations  are  much  scantier  than  one 
might  wish,  but  we  know  that  the  cypress  along  with  a  great  many 
other  Miocene  forest  types  became  exterminated  in  Europe  by 
reason  of  the  vicissitudes  caused  by  the  repeated  ice  sheets  that 
spread  outward  from  the  Scandinavian  highlands  and  from  the 
higher  mountain  masses  farther  south.  Why  the  cypress  did  not 
survive  in  southeastern  Asia  is  a  mystery  and  perhaps  it  will  even- 
tually be  found  in  the  not  yet  thoroughly  explored  upland  valleys 
of  southern  central  China — a  great  plant  refuge  where  recently 
have  been  discovered  the  hickory,  sassafras  and  tulip-tree,  and  many 
other  plants  like  magnolias,  maples  and  ashes  that  serve  to  em- 
phasize the  long  known  and  very  striking  paralleHsms  between 
the  existing  floras  of  southeastern  Asia  and  southeastern  North 
America. 


64  TREE   ANCESTORS 

In  North  America  the  forests  shrank  southward  before  the  ice 
sheets  and  spread  northward  during  the  Interglacial  periods.  At 
those  times  of  pressure  from  the  north  on  the  plant  populations 
of  eastern  North  America — forests  had  already  practically  disap>- 
peared  from  what  is  now  and  was  then  the  plains  country — many 
tree  species  ranged  southward  along  the  highlands  to  Central 
America.  Among  these  southward  spreading  migrants  was  the 
cypress  which  left  a  species  stranded  there  as  it  were  when  ch- 
matic  changes  occurred  in  the  region  which  today  separates  the 
range  of  the  bald  cypress  from  that  of  the  Mexican  cypress. 

A  very  large  number  of  fossil  swamp  deposits  where  once  were 
cypress  bays  have  been  uncovered  by  artificial  excavations  or  by 
natural  erosion  of  sea  cut  scarps  or  river  cutting  in  the  Pleistocene 
deposits  of  the  Coastal  Plain.  These  old  cypress  swamps,  often 
•with  the  stumps  of  trees  of  great  size,  8  to  10  feet  in  diameter,  are 
especially  comm^on  in  the  tidewater  country  of  Maryland  and 
Virginia.  The  remains  of  one  of  these  cypress  swamps  has  been 
exposed  by  recent  cutting  of  the  Rappahannock  River  a  short 
distance  above  the  town  of  Tappahannock,  Virginia.  The  peat 
which  represents  the  old  swamp  muck  is  exposed  for  a  thickness 
of  4  or  5  feet  and  is  overlain  by  from  15  to  20  feet  of  sand  and  clay. 
Associated  with  the  cypress  stumps,  cone  scales,  and  more  rarely 
leaves  and  catkins,  are  often  found  hickory  and  beech  nuts,  grape 
and  gum  seeds,  beetle  wings  and  insect  galls,  and  other  evidences 
of  the  contemporaneous  life. 

Another  Pleistocene  cypress  swamip  on  the  Rappahannock 
River  near  Waterview,  shows  the  old  stumps  in  their  peaty  matrix 
planed  off  and  covered  by  thick  beds  of  sand — a  readable  record 
of  a  once  sinking  area  where  the  estuary  waters  advanced  over 
the  swamp,  killing  the  seedlings  and  wasting  the  old  trees,  the 
surface  having  been  eventually  scoured  smooth  by  the  waves  that 
deposited  the  sands  layer  upon  layer  with  the  continued  subsidence. 
Subsequently  elevation  succeeded  subsidence  and  in  modern  days 
the  river  is  engaged  in  cutting  away  this  fragment  of  Pleistocene 
history. 


THE   BALD   CYPRESS  65 

Sometimes  there  are  successive  levels  of  these  cypress  stumps 
with  their  roots  and  knees  embedded  in  the  impure  peat  as  in  the 
Pleistocene  swamp  which  grew  in  an  old  Cretaceous  basin  near 
Bodkin  Point  on  the  western  shore  of  Chesapeake  Bay,  and  a 
similar  succession  is  shown  in  another  such  swamp  recently  dis- 
covered in  excavating  for  the  foundation  of  a  hotel  in  the  city  of 
Washington.  Another  most  interesting  rehc  of  a  Pleistocene 
cypress  bay  is  one  that  was  discovered  west  of  the  Blue  Ridge  in 
the  Shenandoah  Valley  near  Lexington,  Virginia,  many  miles 
west  of  the  present  range  of  the  species. 

At  the  present  time  the  bald  cypress  is  practically  confined  to 
what  is  known  as  the  Coastal  Plain  and  does  not  extend  its  range 
inland  beyond  the  so-called  Fall  line  which  marks  the  boundary 
between  the  mostly  unconsolidated  rocks  of  the  Coastal  Plain  and 
the  ancient  crystalline  rocks  of  the  Piedmont  Plateau.  But  during 
the  Pleistocene  when  the  Coastal  Plain  region  was  largely  flooded 
by  the  sea,  the  forests  were  forced  inland,  and  the  cypress  evi- 
dently spread  up  the  valley  of  the  James  River  and  through  the 
Gap  in  the  Blue  Ridge  into  the  Great  Valley  of  Virginia.  Other 
Pleistocene  records  of  the  cypress,  far  inland  from  its  present  range 
have  been  found  in  northwestern  Georgia  and  in  central  Alabama. 

Many  other  Pleistocene  records  of  the  cypress  are  outside  the 
Hmits  of  the  present  range,  one  being  as  far  north  as  Long  Branch, 
New  Jersey,  nearly  150  miles  north  of  its  present  northern  limit. 
The  area  of  distribution  of  the  bald  cypress  in  the  area  east  of 
the  Mississippi  River,  and  the  known  Pleistocene  records  are  shown 
on  the  accompanying  sketch  map. 

With  the  melting  of  the  last  Pleistocene  ice  sheet  we  find  evi- 
dence of  cHmatic  conditions  somewhat  warmer  than  those  that 
prevail  at  the  present  time  in  the  same  latitudes.  This  is  shown 
by  various  subf  ossil  records  of  both  terrestrial  and  marine  organisms 
that  have  been  discovered  at  various  points  from  Maryland  to 
Maine,  as  well  as  by  the  isolated  occurrences  of  hving  animals  and 
plants  where  they  have  survived  in  limited  favorable  localities 
many  miles  north  of  their  present  normal  range,  as  in  Essex 
County,  Massachusetts,  and  Newfoundland. 


66 


TREE   ANCESTORS 


At  the  present  time  the  bald  cypress  appears  to  be  perceptibly 
retreating  southward,  particularly  at  its  northern  limit  of  range 
in  southern  Delaware  and  Maryland.     Here  are  to  be  found  traces 


Fig.    11.  Map    of   Southeastern    North    America    SHO\\^NG    Present 

Northern  Limits  of  the  Bald  Cypress  and  Its  Occurrence  in 

THE  Pleistocene  (solid  circles) 


of  trees  where  no  longer  live  trees  exist,  although  they  appear  to 
thrive  when  artificially  planted  as  in  the  parks  of  Baltimore  and 
Washington.     Why  they  do  not  do  so  in  Nature  is  a  mystery, 


THE   BALD   CYPRESS  •     67 

probably  connected  with  lack  of  facilities  for  seeding  and  some 
environmental  factor  affecting  the  vitality  of  the  seedlings  where 
they  do  succeed  in  getting  a  start. 

The  case  of  the  cypress  is  not  an  exceptionable  one  among  trees 
and  its  past  history  will  be  found  to  be  more  or  less  paralleled  by 
many  of  the  forest  trees  that  are  discussed  in  succeeding  chapters, 
whose  ancestors  reach  back  several  milhons  of  years,  and  whose 
present  structures,  habits  and  ranges  are  the  result  of  ages  of 
adjustment  to  the  maze  of  interacting  and  constantly  changing 
environmental  forces  amid  which  they  have  run  their  race — some- 
thing which  I  fancy  is  not  generally  appreciated  by  lovers  and 
students  of  the  modern  trees. 


CHAPTER  DC 

The  Walnuts  and  Hickories 

The  walnut  family,  or  Juglandaceae,  which  includes  the  walnut^ 
butternut,  hickory  and  pignut,  although  a  relatively  small  family^ 
is  by  no  means  as  limited  as  it  seems.  According  to  the  current 
interpretation  of  the  botanists  it  includes  six  groups  of  forms,  or 
genera,  and  these  genera  contain,  altogether,  about  two  score 
different  kinds,  or  species.  They  are  widely  scattered  throughout 
the  warmer  parts  of  the  North  Temperate  Zone,  and  unlike  the 
majority  of  their  associates  they  have  spread  long  distances  south 
of  the  Equator  in  South  America  and  in  the  East  Indies. 

The  walnut  family  is  of  considerable  interest  for  a  variety  of 
reasons,  chief  among  which,  aside  from  the  great  economic  impor- 
tance of  some  of  them,  is  their  long  line  of  extinct  ancestors  reach- 
ing back  some  millions  of  years  to  the  Cretaceous  period,  and  the 
wide  geographical  range  and  abundance  of  these  ancestors,  which 
explain  the  often  curious  distribution  of  the  existing  forms  shown 
on  the  accompanying  maps. 

Not  all  of  the  genera  have  developed  the  same  methods  for  the 
dissemination  of  their  seeds  and  some,  instead  of  forming  the  huge 
nuts  of  our  familiar  walnuts  have  kept  the  seed  part  of  their  fruits 
small  and  light,  thus  enabling  them  to  produce  large  numbers  of 
seeds  with  the  same  amount  of  material  and  expenditure  of  energy 
required  for  a  single  walnut.  Furthermore,  instead  of  depending 
altogether  on  chance  or  hungry  squirrels  for  the  dissemination  of 
their  latent  progeny,  the  bracts  that  are  normally  present  through- 
out the  family  have  been  enormously  developed  and  serve  as  -^ings. 
This  state  of  affairs  is  best  developed  in  those  trees  known  as 
Engelhardtias  and  will  be  referred  to  on  a  subsequent  page. 

The  fruits  unmistakably  indicate  the  genera — those  of  the  hick- 
ory have  smooth  shells  and  a  husk  which  splits  more  or  less  readily — 
the  walnuts  and  butternuts  have  a  pitted  rough  shell  and  an  entire 


THE   WALNUTS   AND  HICKORIES  69 

persistent  husk — the  other  and  less  well  known  genera  have  de- 
veloped more  or  less  winged  fruits  with  characteristic  differences. 
The  leaves  of  all  are  what  is  known  as  pinnately  compound,  that 
is  they  consist  of  two  rows  of  leaflets  regularly  arranged  on  either 
side  of  the  leaf  stalk.  They  are  much  Hke  the  leaves  of  the  ash 
but  the  two  may  be  readily  distinguished  by  being  arranged  on  the 
branches  alternately,  instead  of  opposite  in  pairs  as  in  the  ash. 
There  are  numerous  other  details  that  enable  the  student  to  dis- 
tinguish between  the  leaves  of  the  different  forms,  and  this  is 
fortunate  because  most  fossil  plants  are  represented  by  leaves  in 
the  rocks.  More  rarely  are  fruits  preserved  as  fossils,  and  only  in 
the  most  exceptional  cases  do  we  find  flowers  or  other  parts. 

THE    HICKORIES 

The  hickories  are  now  referred  to  the  genus  Hicoria,  proposed 
in  1808  by  that  romantic  naturaKst  Rafinesque,  although  many 
botanists,  especially  in  the  Old  World,  still  use  the  name  Carya 
proposed  by  the  naturahst  Nuttall  in  1818  and  almost  universally 
used  for  the  hickories  until  about  twenty  years  ago  when  the 
botanists  formulated  rules  governing  such  matters  and  decided 
that  the  names  first  proposed  should  be  the  ones  recognized. 

The  hickories  occupy  a  unique  economic  position,  for  although 
the  consumption  of  their  wood  is  less  in  quantity  than  that  of  some 
of  the  other  hardwoods  such  as  white  oak  or  yellow  poplar,  or  of 
the  various  coniferous  woods  like  the  cypress  or  pines,  it  shares 
with  the  black  walnut  the  distinction  of  being  the  most  costly 
American  wood.  Hickory  wood,  although  not  remarkable  for 
beauty  of  color  or  grain,  will  probably  be  the  most  difficult  wood 
to  replace  when  the  approaching  shortage  becomes  more  acute, 
since  it  combines  weight,  hardness,  stiffness,  strength  and  tough- 
ness to  a  degree  that  is  unequalled  among  commercial  woods.  The 
Forest  Service  estimated  that  the  consumption  of  hickory  for 
lumber,  and  for  such  things  as  spokes,  tool-handles,  rims,  shafts, 
sucker  rods,  etc.,  amounted  to  nearly  five  hundred  million  board 
feet  during  1908,  and  this  exclusive  of  the  large  amount  used  as 


70 


TREE    ANCESTORS 


fuel,  estimated  for  that  year  at  about  a  million  cords— for  hickory 
is  also  the  best  American  fuel  wood. 

With  the  exception  of  a  single  species  (Hicoria  cathayensis)  of 
restricted  range  in  the  provinces  of  Chekiang  and  Kweichow,  China, 
the  existing  hickories  are  entirely  confined  to  North  America,  and 
more  particularly  to  the  eastern  United  States,  although  there  is 
one  in  Mexico  {Hicoria  mexicana),  and  three  or  four  others  reach 


Fig.  12.  Map  Showing  the  Areas  Where  Hickories  Are  Found  at  the 

Present  Time  (solid  black)  and  the  Areas  Over  Which  They 

Are  Known  to  Have  Spread  During  Their  Past  History 


their  northern  limit  of  growth  beyond  the  Great  Lakes  in  eastern 
Canada.  The  hickory  does  not  have  the  legendary  qualities  or  the 
poetic  references  of  many  a  less  noble  tree  largely  because  it  had 
already  become  extinct  in  Europe  before  the  human  race  first 
invaded  that  continent  in  the  days  of  the  Old  Stone  Age.  If  our 
European  ancestors  had  known  hickory  doubtless  it  would  have 
shared  if  not  replaced  the  place  taken  by  such  trees  as  the  oak  or 
the  ash  in  folklore. 


THE   WALNUTS   AND  HICKORIES  71 

The  existing  species  of  hickories  number  from  8  to  15, 
according  to  the  rank  assigned  to  the  varieties  of  the  8  or  9 
easily  distinguished  main  types.  They  fall  naturally  into  two 
groups — the  true  hickories,  and  the  pecan  hickories — groups  which 
were  already  clearly  defined  in  preglacial  Pliocene  times. 

The  true  hickories  are  fine,  slow  growing  trees  in  general  tem- 
perate dry  soils,  and  with  hard  strong  wood.  The  buds  are  full 
with  overlapping  scales,  the  nuts  are  generally  thick  shelled  and 
thick  husked,  and  each  leaf  consists  of  from  three  to  nine  leaflets. 
The  pecan  hickories  are  trees  which  require  warmth  and  moisture, 
and  have  relatively  weak  wood.  The  buds  are  thin  and  narrow 
without  overlapping  scales,  the  nuts  have  thin  shells  and  thin 
husks,  and  the  leaflets  are  numerous,  slender  and  falcate. 

Over  a  score  of  ancestral  fossil  species  are  known.  Unlike  the 
walnut,  the  hickory  is  not  certainly  known  from  the  Cretaceous 
period,  but  it  is  present  in  nearly  every  early  Eocene  deposit  in 
Wyoming  and  on  our  Pacific  coast.  Hickories  occur  in  the  upper 
Eocene  of  Central  Europe  and  our  Gulf  States,  and  there  is  a  fine 
large  leafed  form  in  deposits  of  this  age  at  Kukak  Bay,  Alaska. 
A  form  known  as  Ilicoria  ventricosa  is  very  abundant  in  the  brown 
coal  deposits  of  Europe  of  Oligocene  age.  The  late  Miocene  appears 
to  have  been  the  period  of  widest  extent  of  these  trees,  representa- 
tives having  been  found  throughout  Europe  and  North  America  in 
regions  where  they  no  longer  exist,  as  on  the  former  continent,  or 
in  Oregon,  Cahfornia  and  Colorado. 

During  the  succeeding  Pliocene  period  the  hickories  are  as  abun- 
dant and  vigorous  as  in  the  late  Miocene  in  Europe  although  their 
northern  limit  appears  to  have  become  somewhat  restricted.  Even 
as  late  in  geologic  time  as  the  upper  Pliocene  several  species  were 
abundant  in  Italy  and  Germany,  but  none  survived  the  Ice  Age 
on  that  continent.  A  form  resembling  the  modern  pecan  is  repre- 
sented by  both  leaves  and  nuts  in  a  late  Phocene  coastal  lagoon 
deposit  in  southern  Alabama. 

We  have,  in  America,  numerous  Pleistocene  records,  the  leaves 
being  preserved  in  the  clay  deposits  of  the  river  terraces,  and  the 


72  TREE   ANCESTORS 

nuts  and  husks  in  the  buried  swamp  deposits.  The  following  still 
existing  species  have  been  recorded  from  the  Pleistocene  of  this 
country :  the  White  Hickory  {Hicoria  alba)  from  a  cave  in  Pennsyl- 
vania and  from  the  interglacial  beds  near  Toronto,  Canada;  the 
Water  Hickory  {Hicoria  aquatica)  from  North  Carolina;  the  shag 
bark  {Hicoria  ovata)  from  Pennsylvania,  Maryland  and  North 
Carolina;  and  Hicoria  glabra  from  Pennsylvania,  Maryland,  Vir- 
ginia, and  North  Carolina. 

The  accompanying  map  (fig.  12)  shows  the  area  occupied  by 
the  existing  hickories  in  sohd  black,  and  the  area  within  which 
Tertiary  fossil  forms  have  been  found  by  vertical  lining.  It  seems 
probable  that  extinct  forms  once  spread  eastward  over  Asia  because 
of  the  single  existing  species  in  China  thousands  of  miles  from  any 
of  its  North  American  relatives  but  the  former  continent  has  been 
little  explored  and  no  records  are  known. 

Although  the  Ice  Age  exterminated  the  hickories  throughout 
Europe  and  most  of  Asia  they  survived  safely  in  North  America 
and  are  in  no  danger  except  from  the  axe  of  the  woodman.  Their 
great  tolerance  of  shade  and  their  ability  to  respond  to  the  stimu- 
lus of  increased  light  combined  with  their  longevity  are  important 
factors  in  their  continued  existence.  Although  rodents  consume 
many  of  their  fruits  they  have  probably  done  so  throughout  their 
whole  history,  for  nuts  gnawed  by  squirrels  are  not  infrequent  in 
Pleistocene  deposits.  This  is  not  an  unmixed  evil  for  various 
rodents  not  only  distribute  the  nuts  but  bury  them  in  afterward 
forgotten  places  where  they  are  almost  sure  to  grow.  Before  the 
advent  of  the  ''civilized  axe"  many  venerable  old  giants  were  scat- 
tered through  our  American  forests,  and  there  are  numerous  records 
of  immense  trunks  showing  350  or  more  annual  rings.  There  is 
a  record  of  a  pecan  at  Evansville,  Indiana  which  had  a  trunk  6 
feet  in  diameter  showing  400  growth  rings  showing  that  it  was 
already  a  small  tree  before  Cortez  conquered  Mexico  and  had 
reached  a  considerable  size  by  the  time  the  Pilgrims  landed  at 
Plymouth. 


THE   WALNUTS    AND   HICKORIES  73 

THE   WALNUTS 

Walnuts  belong  to  the  genus  Juglans,  a  contraction  of  Jovis 
glans  or  nut  of  Jupiter,  and  the  specific  name  of  the  species  known 
to  the  Greeks  and  Romans  is  regia,  or  royal,  and  is  fittingly  applied 
to  the  magnificent  tree  which  has  been  so  commonly  planted 
throughout  the  old  world  for  so  many  centuries.  Its  nuts  have 
been  found  around  the  Swiss  lake  dwellings  of  the  NeoHthic  age, 
about  7000  B.C.  Our  two  eastern  American  species  are  equally 
royal  trees.  The  black  walnut  {Juglans  nigra)  ranges  from 
Massachusetts  to  southern  Ontario,  Minnesota  and  eastern  Kansas, 
and  southward  to  Florida  and  Texas.  Its  rich  edible  fruits  and 
handsome  dark  wood  have  made  it  a  favorite  wherever  furniture 
is  used,  and  in  consequence  the  tree  is  becoming  scarce.  It  makes 
a  fine  growth  when  planted  abroad  where  it  is  perfectly  at  home, 
perhaps  because  it  was  a  native  of  Europe  in  preglacial  time,  as 
is  shown  by  the  nuts  preserved  in  the  Pliocene  deposits  of  that 
continent. 

The  white  walnut  or  butternut  {Juglans  cinerea)  yields  a  wood 
that  is  much  inferior  to  that  of  the  Black  Walnut,  but  its  fruit  is 
equally  or  more  attractive.  It  ranges  somewhat  farther  to  the 
northward  and  not  so  far  to  the  southward  as  the  black  walnut, 
being  found  from  New  Brunswick  and  Ontario  to  North  Dakota, 
and  southward  to  Delaware.  In  the  Alleghanian  region  it  extends 
southward  to  Georgia  and  northeastern  Mississippi  and  it  is  also 
found  in  Arkansas.  It  is  distinctly  not  a  coastal  plain  species. 
Like  the  black  walnut  it  is  very  closely  allied  to  certain  preglacial 
Eurasian  fossil  forms. 

There  are  several  other  American  species  with  a  more  Hmited 
range.  All  are  trees,  and  they  include  a  Jamaican  form,  and  one 
or  two  species  found  in  eastern  Brazil  and  in  the  Andes  of  Peru  and 
Bolivia.  A  species  of  northern  Mexico  {Juglans  rupestris)  ex- 
tends into  Arizona,  New  Mexico  and  the  Rio  Grande  part  of  Texas, 
and  there  is  a  single  species  {Juglans  calif ornica)  along  the  Pacific 
coast  in  Cahfornia.  The  range  of  the  latter  is  limited  and  its 
seedlings  are  scarce — the  nuts  being  largely  consumed  by  rodents. 


74 


TREE   ANCESTORS 


There  is  also  a  walnut  on  the  opposite  shores  of  the  Pacific  in 
Manchuria  {Juglans  mandchurica)  and  a  second  in  Japan  (Juglans 
sieboldiaiia) . 

The  genus  is  apparently  one  of  the  earliest  of  our  still  existing 
trees  to  appear  in  the  fossil  record,  leaves  suggesting  it  having  been 
found  in  the  Middle  Cretaceous.  It  is  well  represented  in  fossil 
floras  from  the  base  of  the  Upper  Cretaceous  to  the  present,  the 
former  horizon  furnishing  several  different  forms,  one  of  which 
named  Juglans  arctica  ranges  from  western  Greenland  to  Alabama 


Fig.  13.    Map  Showing  Present  Range  of  the  Walnuts  (solid  black) 

AND  the  Area  Over  WracH  They  Are  Known  to  Have  Spread 

During  Their  Past  History  (lined) 


along  the  Atlantic  coast,  and  furnishes  a  striking  illustration  of 
the  difference  between  Cretaceous  and  present  day  climates. 

There  are  about  25  species  of  walnut  recorded  for  Eocene  times 
and  at  that  time  they  are  well  distributed  over  the  whole  Northern 
Hemisphere.  They  are  found  from  the  Mexican  Gulf  region  to 
Alaska  and  Greenland  in  North  America;  and  from  Sachalin 
Island  off  the  east  coast  of  Asia  to  western  Europe. 


THE   WALNUTS   AND  HICKORIES  75 

The  Oligocene  walnuts  are  not  quite  so  plentiful  as  are  those  of 
the  Eocene  and  their  records  are  almost  entirely  confined  to  the 
Old  World.  This  is  undoubtedly  merely  an  expression  of  the 
incompleteness  of  the  geological  records  of  this  time  in  North 
America  where  there  are  practically  no  known  plant  beds  of  this 
age. 

The  Miocene  has  furnished  upwards  of  two  score  species,  the 
majority  of  which  are  Old  World  forms  distributed  from  Japan 
on  the  East  to  western  Europe.  This  again  is  due  more  to  lack 
of  records  in  North  America  rather  than  to  the  absence  of  walnuts 
at  that  time.  There  are  Miocene  species  known  from  Idaho, 
several  from  California  and  Oregon,  and  no  less  than  four  have 
been  found  in  the  lake  beds  at  Florissant,  Colorado. 

The  PHocene  species  are  also  numerous,  a  number  of  them  having 
survived  unchanged  from  Miocene  times.  In  all  about  25  differ- 
ent forms  have  been  recorded  from  Pliocene  deposits  and  several 
of  these  are  very  close  if  not  absolutely  identical  with  still  existing 
species.  From  the  late  Pliocene  of  Germany  nuts  have  been  col- 
lected from  the  lignite  deposits  which  are  exactly  like  those  of 
our  present  day  black  walnut  and  butternut,  and  sirnilar  nuts 
occur  in  deposits  as  young  as  the  Pleistocene  at  Aldan  in  Siberia. 

Walnuts  are  not  common  in  the  knowm  Pleistocene  deposits, 
but  the  fruit  of  Juglans  regia  is  recorded  from  beds  of  tliis  age  in 
southern  France,  and  our  black  walnut  has  been  found  in  the 
late  Pleistocene  of  Maryland  and  Alabama,  both  occurrences  being 
based  upon  the  characteristic  nuts  preserved  in  the  impure  peat  of 
buried  swamp  deposits. 

The  European  walnut,  although  it  is  extensively  planted  through- 
out southern  Europe  and  the  Orient,  is  now  native  in  only  the  region 
from  Greece,  where  it  is  mentioned  by  Theophrastus,  eastward 
through  Asia  Minor,  Transcaucasia,  the  northwestern  Himalayan 
region  and  in  northern  Burma,  although  it  may  eventually  be 
discovered  in  the  mountains  of  China.  It  was  not  introduced  into 
Britain  until  the  sixteenth  century.  In  recent  geological  times  its 
range  has  probably  become  greatly  restricted  since  in  preglacial 
times  it  is  known  to  have  been  present  in  central  France     A  con- 


76 


TREE    ANCESTORS 


siderable  number  of  occurrences  have  been  recorded  from  the 
Pliocene  of  that  region  and  the  Auvergne  was  evidently  clothed 
with  a  considerable  stand  of  walnut  before  the  advent  of  the  human 
race.  During  the  Pleistocene  this  species  left  its  remains  at  a 
number  of  locaUties  in  northern  Italy,  in  Hanover,  in  southern 
France  (Provence),  and  nuts  found  in  the  Swiss  lake  dwellings 
were  undoubtedly  from  wild  trees  and  furnished  part  of  the  dietary 


r-^^^xW 

^' 

""^o 

-,,^1 

c 

V-. 

i^V  ^   "f^hAYHT^^ 

df' 

^^ 

^s^ 

^ 

lmITT]  ^^ 

■:W 

V 

1- 

\J 

f\ 

^H^    ELrX^elKardtio. 

~-<^^'^.J....-- 

1^ 

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/^ 

K'  / 

Fig.   14.  Map  Showing  the  Areas  of  Distribution  of   Engelhardtia, 

Oreomunnea,  Platycarya  and  Pterocarya  (solid  black)  and  the 

Area  Over  Which  They  Are  Known  to  Have  Spread 

During  Their  Past  History 

Pterocarya   is   indicated  by    vertical   lining  and  Engelhardtia    (including 
Oreomunnea)  by  horizontal  lining. 


of  the  first  race  of  which  we  have  record  who  had  domesticated 
animals  and  practiced  even  a  rude  agriculture. 

The  manner  in  which  the  fossils  enable  us  to  obtain  a  vista  into 
the  life  of  bygone  days  is  furnished  by  recent  discoveries  in  the 
Egyptian  desert.     At  a  time  (latest  Eocene  or  earliest  Oligocene) 


THE   WALNUTS    AND   HICKORIES 


77 


when  Libya  was  separated  from  Europe  and  Asia  by  a  vast  Mediter- 
ranean sea  the  Fayum  was  a  delta  with  a  heavy  rainfall,  clothed 
with  forests  of  an  Indo-Malayan  type,  and  inhabited  by  ancestral 
elephants  and  other  curious  forms  of  ancient  animal  life.  No  less 
than  8  kinds  of  figs,  as  well  as  laurels  and  camphor  trees  have 
been  described  from  this  now  arid  and  desiccated  region,  and  among 
these  a  species  of  walnut  furnishes  a  striking  commentary  on  the 
changes  which  time  has  wrought  in  this  region. 


Fig.  15.  Winged  Fruit  of  Engelhardtl4  from    the   Lower  Eocene  of 
Mississippi 


I  have  attempted  to  give  a  graphic  summary  of  our  knowledge 
of  the  present  and  past  distribution  of  the  walnuts  in  the  accom- 
panying sketch  map  (fig.  13)  where  the  areas  of  distribution  of  the 
existing  forms  (somewhat  exaggerated)  are  shown  in  solid  black. 
It  is  possible  that  the  part  of  the  range  of  Juglans  regia  in  southern 
Asia  should  be  extended  eastward  over  Tibet  through  northern 
China  to  Japan.  All  of  the  known  fossil  occurrences  of  walnuts 
have  been  plotted  and  are  enclosed  within  the  vertically  lined 
area.  Probably  the  southern  boundary  of  this  area  should  be 
extended,  far  enough  at  least  to  include  the  present  homes  of  the 


78  TREE   ANCESTORS 

existing  South  American  species.  It  is  readily  apparent  from  this 
map  that  the  modern  species  with  their  disconnected  distribution 
represent  the  segregated  remnants  of  a  once  worid  wide  distribu- 
tion, and  that  the  Glacial  period  or  Ice  Age  was  as  unimportant  an 
incident  in  their  history  in  North  America,  where  there  were  no 
mountain  or  water  barriers  to  cut  ofif  their  retreat  before  the  ice, 
as  it  was  a  tragic  event  in  Europe,  where  from  Gibraltar  to  the 
Caspian  a  succession  of  sea  and  mountains  blocked  their  retreat 
to  the  southward  greatly  restricting  the  range  of  Juglans  regia, 
and  altogether  exterminating  one  or  two  additional  species  of 
walnut,  as  well  as  the  European  hickories  and  a  host  oi  other  trees. 

The  other  members  of  this  ancient  and  noble  family  are  no  longer 
present  in  our  American  forests,  but  some  of  them  once  Hved  here 
in  the  distant  past,  and  I  have  introduced  a  map  of  their  present 
and  past  distribution  to  show  how  imperfect  is  our  knowledge  if 
it  be  confined  merely  to  the  present,  and  to  illustrate  the  principle 
that  closely  related  trees,  or  any  other  kinds  of  organisms  for  that 
matter,  which  are  now  found  on  perhaps  opposite  sides  of  the  globe, 
are  descended  from  common  ancestors  which  once  spread  over  the 
intervening  lands. 

These  members  of  the  family  now  extinct  in  temperate  North 
America  are  Platycarya,  a  small  tree  of  Japan  and  northern  China 

Fig.  16.  Some  Fossil  Leaves  and  Nuts  of  Walnut    (About  ^ 
Natural  Size) 

1.  Juglans  arctica  Heer  from  the  Upper  Cretaceous  of  Western  Greenland. 

2.  Juglans  schimperi  Lesquereux  from  the  Eocene  of  Louisiana. 

3.  Juglans  rugosa  Lesquereux  from  the  Eocene  of  Wyoming. 

4.  Juglans  acuminata  Alex.  Braun  from  the  Miocene  of  Switzerland. 

5.  Juglans  paviaefolia  Gaudin  from  the  Pliocene  of  Italy. 

6.  Juglans  sieboldiana  Maximowicz,  nut  from  the  late  Tertiary  of  Japan. 

7.  Juglans  cinerea  Linne,  nut  from  the  Pleistocene  of  Aldan  River,  central 
Siberia. 

8.  Juglans  cinerea  Linne  var  mucronata,  nut  from  the  upper  Pliocene 
lower  Main  valley,  Germany. 

9a,  9b.  Juglans  cinerera  Linne  var  tnucronata,  surface  and  interior  view  of  a 
nut  from  the  Wetterau  lignites  of  Germany. 


Fig.  16 
79 


80  TREE    ANCESTORS 

altogether  lacking  kno\\Ti  fossil  representatives;  Pterocarya,  with 
a  few  species  in  Trans  Caucasia,  China  and  Japan,  represented  in 
the  Tertiary  in  both  Europe  and  North  America;  and  Engelhardtia 
(including  Oreomunnea)  which  is  now  found  in  Asia  from  the  Hima- 
layas to  Java  and  the  Philippines,  and  in  the  mountains  of  Central 
America  on  the  opposite  side  of  the  world.  Engelhardtia  illus- 
trates the  extreme  development  of  reduced  fruits  and  enlarged 
wings,  and  considerable  of  its  geologic  history  is  known.  It  appears 
first  in  the  earliest  Tertiary  along  the  shores  of  the  then  enlarged 
Gulf  of  Mexico  in  Mississippi  and  Arkansas.  Somewhat  later 
it  is  found  on  our  Pacific  coast  and  in  Europe.  A  fossil  winged 
fruit  from  Mississippi  is  shown  in  the  accompanying  figure  to  illus- 
trate its  unlikeness  to  a  walnut  or  hickory  nut.  These  winged 
fruits  are  something  like  those  of  the  hornbeam  (CarjDinus)  of  the 
birch  family,  but  the  proportions  and  veining  are  different,  as  is 
also  the  fruit  itself,  and  the  wings  of  the  hornbeam  are  toothed  and 
not  entire. 

Forestry  experts  warn  us  that  the  commercial  hickory  is  growing 
scarce,  just  as  the  black  walnut  is  already  scarce.  Aside  from 
our  enjo}mient  of  their  nuts  and  the  very  practical  ends  which  the 
wood  fulfills  we  should  never  forget  the  sentiment  which  attaches 
to  a  family  of  such  magnificent  trees,  a  family  with  an  ancestry, 
as  we  have  seen,  extending  back  millions  of  years  to  a  far  off  time 
when  the  dominant  animal  population  of  the  globe  was  the  un- 
couth reptiles  of  the  Cretaceous,  a  time  when  the  evolution  of  the 
mammalia  had  not  yet  been  wrought  out,  and  when  man  was  a 
far  distant  promise,  not  even  hinted  at  in  the  teeming  life  of  that 
age. 

Although  we  can  never  hope  to  bring  back  the  primeval  forests 
of  our  ancestors,  and  it  is  probably  best  so,  we  can  at  least  use  the 
intelhgence  wliich  the  race  has  so  slowly  acquired  through  the  ages 
in  conserving  these  magnificent  tree  relics  of  former  times." 


CHAPTER  X 

The  Willows  and  Poplars 

The  willows  and  poplars,  which  constitute  a  separate  family  and 
order  of  plants,  are  characterized  by  a  number  of  well  marked 
morphological  features.  They  have  soft  hght  wood,  astringent 
bark,  watery  sap,  scaly  buds  and  deciduous  leaves — short  stalked 
in  the  willows,  long  stalked  in  the  poplars — arranged  alternately 
and  with  stipules.  The  flowers  are  in  the  form  of  catkins  which 
bloom  in  the  early  spring  in  advance  of  the  unfolding  of  the  leaves. 
These  catkins  are  generally  upright  in  the  willows  and  pendulous 
in  the  poplars,  and  the  male  and  female  are  borne  on  different 
plants.  The  seeds,  which  are  tufted  with  silky  or  cottony  hairs, 
are  formed  in  one  celled,  two  to  four  valved  capsules,  and  are 
dispersed  by  the  winds. 

By  reason  of  their  rapidity  of  growth,  tolerance  of  moisture 
(the  name  Salix  is  said  to  be  derived  from  the  Celtic  sal  =  near  and 
/w  =  water)  and  their  great  adaptability  to  all  kinds  of  soils  they 
occur  in  a  variety  of  situations  and  the  different  members  of  the 
family  are  found  from  the  north  polar  region  to  the  equator  and 
beyond.  They  are  gregarious  because  of  the  ease  with  which  they 
grow  from  suckers  and  sprouts,  their  great  vitality  and  free  forma- 
tion of  shoots  and  seeds.  About  the  only  inimical  condition  that 
proves  fatal  is  shade,  of  which  they  are  very  intolerant,  hence  in 
the  natural  growth  of  the  forest  they  tend  to  become  replaced  by 
slower  growing  trees  which  eventually  overtop  them.  Thus  in 
time  they  become  restricted  (especially  the  willows)  to  river  bars, 
mud  banks,  peat  bogs,  mountain  tops  and  similar  unfavorable  situa- 
tions. Both  willows  and  poplars  are  very  fast  growers  and  both 
are  relatively  short  lived.  The  majority  are  not  tall  trees  and  the 
seeds  quickly  lose  their  vitality  and  the  trees  are  much  damaged 
by  winds  because  of  their  brittle  wood. 

The  willows  are  far  more  diversified  and  more  widely  distributed 
than  the  poplars,  and  the  facility  with  which  hybrids  are  formed 

81 


82  TREE   ANCESTORS 

and  the  trivial  specific  differentiation  of  so  many  of  the  species 
makes  them  a  very  baffling  group  for  the  systematic  botanist. 
Although  both  willows  and  poplars  come  from  a  very  old  stock,  a 
stock  as  old  as  any  of  our  trees  except  the  conifers,  and  one  much 
more  ancient  than  that  of  our  familiar  warm  blooded  animals,  the 
willows  seem  to  have  reached  the  zenith  of  their  development  in 
post  glacial  times,  while  the  poplars  on  the  other  hand  were  more 
varied  and  widespread  in  earlier  geologic  times. 

THE    WILLOWS   (sALIx) 

The  name  willow  suggests  to  most  dwellers  in  temperate  climes 
the  graceful  pendulous  branches  of  the  weeping  or  so-called  Baby- 
lonian willow  or  the  silky  catkins  of  the  pussywillows  collected 
in  the  early  springs  of  our  childhood  days.  We  associate  the 
gnarled  trunks  of  willows  with  Corot's  paintings,  or,  if  we  have 
chanced  to  live  in  certain  districts,  we  think  of  the  willow  chiefly 
as  a  cultivated  crop  the  shoots  of  which  are  utilized  for  the  making 
of  baskets,  wicker  furniture  and  willow-ware.  Possibly  in  youth- 
ful chemical  experiences  we  have  tried  to  make  gunpowder  from 
willow  charcoal,  or  charcoal  crayons,  and  what  American  boy  does 
not  know  that  willow  wood  makes  good  baseball  bats  or  that 
whistles  can  be  manufactured  from  the  twigs.  Willow,  of  course, 
enters  into  a  great  variety  of  uses,  some  of  which  will  be  enumerated, 
but  probably  its  oldest  use  was  the  plaiting  of  its  shoots  into  bas- 
kets or  similar  articles.  I  have  no  doubt  that  the  men,  or  more 
likely  the  women,  of  the  Old  Stone  Age  made  baskets  of  willow 
twigs,  since  plaiting  is  part  of  the  art  of  the  most  primitive  of  exist- 
ing peoples.  Basket  willows  were  cultivated  by  the  Romans, 
who  used  the  shoots  for  making  bee  hives,  baskets,  garden  and 
vineyard  trellises.  The  light  elastic  v/ood  they  covered  with  raw- 
hide and  bossed  with  brass  for  the  shields  of  their  legionaries.  Pliny 
mentions  four  species  of  willow  so  used  in  his  day  {Salix  fragilis, 
S.  purpurea,  S.  amygdalina,  and  S.  viminalis). 

During  the  Middle  Ages  the  basketmakers  guilds  were  of  con- 
siderable importance  particularly  in  France,   Germany  and  the 


THE   WILLOWS   AND    POPLARS  83 

Low  Countries,  These  sank  into  insignificance  during  the  seven- 
teenth and  eighteenth  centuries  when  they  were  replaced  by  itiner- 
ant basket  makers,  whose  activities  sufficed  for  supplying  the  local 
demand.  With  the  advent  of  the  factory  system  and  the  simul- 
taneous great  increase  in  trade  and  communications,  the  demand 
for  baskets  and  hampers  for  parcel  sliipments  of  all  kinds  gave  a 
great  impetus  to  basket  making,  particularly  in  Europe  where 
labor  was  so  much  cheaper  than  in  America.  This,  coupled  with 
the  constantly  increasing  popularity  of  wicker  furniture,  has  re- 
sulted in  a  constant  and  increasing  demand  for  willow  shoots. 
Napoleon's  embargo  stimulated  willow  culture  in  Britain,  and 
considerable  areas  in  our  own  eastern  States  have  long  been  de- 
voted to  this  purpose,  usually  however  with  little  selection  as  to 
species  cultivated  or  cultural  methods. 

Willows,  particularly  pollard  willows,  play  a  great  part  in  land- 
scape painting,  especially  in  the  art  of  France  and  that  of  the  Low 
Countries  where  they  are  such  famiHar  objects  lining  roads,  canals 
and  drainage  ditches.  The  association  of  sadness  with  willows 
probably  survives  from  the  captivity  of  the  children  of  Israel 
"by  the  rivers  of  Babylon."  At  the  Feast  of  the  Tabernacles  they 
were  commanded  to  take,  on  the  first  day,  branches  of  palm  trees 
and  willows  of  the  brook.  The  so-called  weeping  or  Babylonian 
willow  is  a  favorite  graveyard  tree,  so  much  so  that  "she  is  in  her 
willows"  was  a  common  expression  applied  to  widows  throughout 
rural  England.  Shakespeare  has  Ophelia  drowned  by  a  willow, 
and  Fuller  says  of  it:  "A  sad  tree,  whereof  such  who  had  lost  their 
love  make  their  mourning  garlands." 

There  are  more  than  200  existing  species  of  willows  of  all  grades 
of  stature,  and  while  we  think  of  them  as  especially  characteristic 
of  the  North  Temperate  Zone  they  are  by  no  means  confined 
to  it  but  range  from  the  Arctic  Circle  southward  across  the  equa- 
torial regions  into  the  South  Temperate  Zone.  In  America  there 
are  upwards  of  100  species,  ranging  in  size  from  tiny  plants  a  few 
inches  high  under  the  Arctic  Circle  to  trees  140  feet  tall  and  4  feet 
in  diameter  in  more  genial  situations,  as  in  the  bottom  lands  of 
the  lower  Mississippi  V^alley.     About  a  score  of  these  are  trees. 


84  TREE   ANCESTORS 

They  are  found  from  tidewater  to  the  snowHne  of  mountains  and 
from  the  Arctic  through  Canada  and  the  United  States  to  the  Gulf, 
and  from  the  Alantic  to  the  Paciiic.  They  occur  in  the  West  Indies 
and  Central  America  and  southward  to  the  Chilean  Andes.  In 
the  Old  World  they  range  from  Arctic  Europe  and  Asia  southward 
over  both  of  those  continents  to  Madagascar  and  South  Africa, 
and  from  the  Himalayan  region  southeastward  through  Malayasia 
to  Java. 

Aside  from  the  older  uses  of  willow  as  cover  to  prevent  erosion 
or  for  basketry  or  charcoal,  its  utilization  for  lumbering  has  had  a 
relatively  modern  development.  At  the  present  time  low  grades 
are  largely  used  for  box  and  cooperage  material  while  the  higher 
grades  are  employed  for  furniture  drawers  and  backing,  as  well 
as  for  refrigerators,  cabinet  work  and  cheap  furniture.  Willow 
planking  is  satisfactory  for  purposes  where  strength  is  not  required, 
since  it  does  not  warp,  splinter  or  check,  and  this  property  deter- 
mines its  use  for  boat  parts  such  as  keels,  paddles,  etc.,  and  for  ath- 
letic goods,  cutting  boards,  toys,  etc.  Large  quantities  are  also 
consumed  every  year  by  excelsior  mills. 

The  oldest  known  willows,  not  certainly  identified,  are  recorded, 
along  with  the  early  representatives  of  other  dicotyledonous  plants, 
from  the  late  Lower  Cretaceous  of  Portugal.  During  the  earher 
part  of  the  Upper  Cretaceous,  the  time  when  the  remains  of  the 
higher  or  socalled  flowering  plants  first  become  prominent  in  the 
geological  record,  a  great  many  species  of  supposed  willows  have 
been  found.  Upwards  of  a  score  of  forms  have  been  described, 
and  the  ancestral  stock  during  these  early  days  must  have  pos- 
sessed some  of  the  vitality  that  marks  the  recent  forms,  for  it  spread 
rapidly  over  North  America  as  well  as  Europe  and  probably  over 
Asia  as  well,  although  there  are  no  kno\\ii  records  from  the  last 
continent.  It  should  be  noted  that  four-fifths  of  the  known  Cre- 
taceous species  are  North  American  and  that  none  have  been  found 
in  the  prohfic  Cretaceous  plant  beds  of  Greenland,  although  pop- 
lars appear  to  have  been  abundant  at  that  time  in  the  far  North. 

Botanists  are  divided  in  their  interpretation  of  the  willow  flower, 
some  regarding  its  simphcity  as  a  primitive  character  and  others 


THE    WILLOWS    AND    POPLARS  85 

regarding  it  as  reduced  by  evolution  from  a  more  complex  type. 
Whichever  view  is  correct  the  willows  undoubtedly  appear  early 
in  the  geological  record. 

The  oldest  Tertiary,  or  Eocene,  deposits  have  furnished  about 
25  species  of  willows,  the  records  including  all  of  the  continents  of 
the  Northern  Hemisphere.  Willows  had  now  reached  Greenland, 
where  five  different  species  have  been  discovered.  Other  Arctic 
lands  also  shared  this  invasion,  since  willows  have  been  found  in 
beds  of  this  age  in  Alaska,  at  the  mouth  of  the  Mackenzie  River, 
in  Iceland  and  Spitzbergen.  The  climate  of  the  earth  seems  to 
have  been  more  equable  during  Eocene  times  since  we  find  many 
sub-tropical  plants  in  the  Mississippi  valley  and  as  far  north  as 
southern  England,  and  the  Arctic  lands  at  this  time  were  clothed 
with  dense  forests  of  temperate  types. 

The  Oligocene,  which  succeeds  the  Eocene  in  the  Tertiary 
sequence,  was  a  time  of  prevailingly  marine  deposition  in  North 
America  so  that  few  fossil  plants  are  known  and  there  is  only  one 
willow  among  them,  although  doubtless  willows  still  flourished 
since  they  are  common  in  succeeding  deposits.  In  Europe  about 
half  a  dozen  species  are  known  from  the  Oligocene  rocks. 

The  next  period — the  Miocene — was  a  time  of  great  variety  and 
luxuriance  of  tree  growth.  Between  forty  and  fifty  different  willows 
are  known  and  the  actual  number  in  existence  must  have  been  much 
greater  for  when  we  get  a  glimpse  into  the  past  in  an  otherwise 
unknown  area,  hke  that  furnished  by  the  tiny  lake  basin  at  Floris- 
sant in  the  Colorado  Rockies  we  find  an  abundance  of  willows — ^five 
having  been  described  from  Florissant.  They  are  equally  abund- 
ant in  the  lake  beds  and  elsewhere  throughout  Europe.  A  few 
are  known  from  eastern  Asia  and  in  America  they  occur  in  Vir- 
ginia on  the  East  coast  and  in  Oregon  and  California  on  the  Pacific 
coast. 

The  Miocene  was  succeeded  by  the  Pliocene  period,  a  time  during 
which  the  forests  of  the  Miocene  continued  practically  unchanged. 
Many  willows  whose  characters  foreshadow  their  existing  descend- 
ants are  known  from  Asia  Minor  to  Spain,  but  unfortunately  for 
our  history  the  American  PHocene  deposits  are  for  the  most  part 


86  TREE    ANCESTORS 

marine  marls  so  that  the  American  Pliocene  plant  record  is  almost 
a  blank,  although  we  know  that  the  familiar  types  must  have  been 
present  since  willows  are  abundant  in  the  next  or  Pleistocene  period. 

The  Pleistocene,  or  period  of  continental  glaciers,  was  an  epic 
time  for  all  plants  and  animals,  for  it  was  a  time  during  which  ice 
sheets  many  feet  in  thickness  gradually  accumulated  in  northern 
America  and  Europe  and  in  the  more  elevated  mountains.  After 
fluctuating  near  a  maximum  for  some  thousands  of  years  these 
ice  sheets  gradually  disappeared  and  were  followed  by  a  long  genial 
interglacial  stage.  This  great  accumulation  and  southward  ad- 
vance of  the  ice  was  repeated  four  times  and  the  last  ice  sheet  has 
been  gone  only  a  few  thousand  years.  During  these  changing 
times  all  life  forms  were  subjected  to  new  competitions  and  great 
stresses,  hence  many  forms  succumbed.  Others  shifted  back  and 
forth  with  the  shifting  climatic  conditions  and  still  survive.  A 
great  many  still  existing  species  of  willows,  as  well  as  other  trees, 
make  their  appearance  in  the  Pleistocene  bogs,  lake  beds  and  river 
terrace  deposits  and  thus  serve  to  record  the  gamut  of  changing 
environments.  We  find  for  example  the  tiny  Arctic  willows  like 
Salix  polaris,  which  today  occurs  in  the  Scandinavian  mountains 
and  reaches  its  southern  limits  in  the  tundras  along  the  Arctic 
coast  of  Russia,  present  in  the  Transylvanian  and  Swiss  Alps, 
throughout  Britain,  southern  Sweden,  Denmark  and  the  north 
German  plain,  associated  with  other  plants  of  the  far  north  such 
as  Dryas  and  animals  like  the  Arctic  fox  and  lemming. 

The  accompanjdng  sketch  map  of  Europe  shows  the  unusual 
climatic  conditions  which  enabled  this  far  northern  form,  now 
confined  to  the  lined  area  on  the  map,  to  extend  southward  almost 
to  the  Mediterranean.  This  and  other  herbaceous  or  shrubby 
species  of  Arctic  willows  are  found  at  innumerable  locaHties  through- 
out central  and  northern  Europe,  where  the  deposits  of  this  age 
have  been  so  intensively  studied.  The  conditions  were  dupHcated 
in  North  America  but  as  we  have  devoted  so  little  study  to  the 
life  of  our  Pleistocene  deposits  it  is  not  possible  to  obtain  adequate 
records  of  the  distribution  of  our  Pleistocene  plants. 


THE   WILLOWS   AND   POPLARS 


87 


Fig.  17.   Sketch  Map  of  Europe  Showing  the  Southern  Limits  of  the 

Continental  Ice  Sheet,  the  Present  Distribution  (lined  areas)  and 

THE  Pleistocene  Occurrences  of  Salix  polaris  (Modified 

FROM  Nathorst,  1891) 

1.  Vicinity  of  Edinburgh. 

2.  Localities  in  Yorkshire. 

3.  Localities  in  Norfolk  and  Suffolk. 

4.  Devonshire. 

5.  Numerous  localities  in  the  Alps. 

6.  Localities  in  Bavaria. 

7.  Localities  in  Jutland. 

8.  Localities  in  Zeeland. 

9.  Numerous  localities  in  North  Germany. 

10.  Localities  in  Esthonia,  Livonia  and  Vitebsk. 

11.  Numerous  localities  in  Schonen,  Gotland  and  Jemtland. 

12.  Felek  in  Hungary. 


88  TREE    ANCESTORS 

Over  twenty  kinds  of  willows  have  been  discovered  in  the  Pleis- 
tocene deposits  and  only  two  or  three  of  these  are  extinct  species. 
The  details  of  their  present  range  and  Pleistocene  occurrences  are 
too  extensive  for  the  present  sketch  so  that  only  a  few  will  be 
mentioned.  One  or  the  other  of  the  four  herbaceous  small  leafed 
Arctic  and  Alpine  species  Salix  herbacea,  S.  polaris,  S.  retusa  and 
S.  reticulata  are  found  in  Pleistocene  deposits  as  far  south  as  New 
York  state  in  this  country,  and  Switzerland  and  Galicia  in  Europe. 
Three  of  them  occur  in  Germany.  The  northern  peat  bog  species 
Salix  repens  and  5.  myrtilloides  are  both  found  in  England.  The 
sub-Arctic  species  ^a/z:!;  aurita  and -5.  caprea  occur  respectively  in 
England  and  Denmark.  The  osier  or  basket  willow  is  recorded 
from  France  and  Wiirttemburg,  and  a  very  similar  form  occurs  in 
the  Pleistocene  deposits  of  North  Carolina  and  Kentucky.  The 
white  willow  {Salix  alba)  and  the  crack  willow  {Salix  fragilis)  both 
occur  in  France  and  Wiirttemburg.  With  the  amelioration  of 
conditions  following .  the  last  retreat  of  the  ice  the  Arctic  forms 
withdrew  to  the  far  North  with  the  sub-Arctic  and  cool  temperate 
species  in  their  wake,  and  these  far  northern  forms  are  circumpolar 
at  the  present  time,  although  those  willows  that  attain  to  the 
stature  of  trees  and  inhabit  the  Temperate  Zone  are  different  in 
each  of  the  three  continents  of  the  Northern  Hemisphere. 

THE   POPLARS   (POPULUS) 

The  poplars,  although  they  show  their  community  of  origin 
with  the  willows,  differ  from  them  sufficiently  to  be  readily  dis- 
tinguishable. They  are  all  trees  and  on  the  whole  average  larger 
than  the  willows.  The  catkins  are  pendulous  instead  of  erect; 
there  is  a  rudimentary  perianth  or  flower  envelope,  and  the  bracts 
of  the  flowers  are  toothed  or  cleft  instead  of  entire  as  in  the  willows; 
the  leaves  are  usually  broad  instead  of  narrow,  being  ovate  or 
deltoid  and  often  cordate,  and  the  leaf-stalks  are  long  and  often 
flattened — a  feature  well  exemplified  in  the  quaking  aspen. 

The  generic  name  Populus  is  of  obscure  etymology  but  was  the 
classical  name  of  the  poplar,  of  which  there  are  several  European 
species.     The  most  important  of  these  is  the  white,  silver  poplar, 


THE   WILLOWS    AND   POPLARS  89 

or  abele  {Populus  alba),  a  large  tree  of  the  central  and  southern 
parts  of  that  continent.  The  black  poplar  is  also  a  large  tree  of 
central  and  southern  Europe  and  Asia.  An  aspen  (Populus  trem- 
iila)  occurs  in  central  and  northern  Europe,  ranging  eastward  to 
Japan,  and  there  are  a  number  of  additional  European  species, 
including  the  downy  poplar  {Populus  canescens);  Populus  monilifera, ' 
which  furnished  the  poplar  wood  of  the  Romans ;  and  the  so-called 
Lombardy  poplar  (Populus  fastigiata)  so  often  planted  in  this 
country  as  a  screen  or  ornamental  tree.  The  last  is  probably  of 
oriental  origin  despite  its  name,  coming  originally  from  the  region 
of  the  Vale  of  Kashmir,  since  it  seems  to  have  been  unknown  in 
Italy  in  Pliny's  time.  It  was  unknown  in  England  in  Evelyn's 
day  and  was  introduced  into  that  country  about  the  middle  of 
the  1 8th  century.  Populus  euphratica  of  North  Africa,  the  Altai  and 
Himalayan  region  is  believed  to  have  been  the  weeping  willow  of 
the  Scriptures  and  its  wood  along  with  that  of  the  date  palm 
furnished  the  rafters  for  the  buildings  of  Nineveh.  The  bud  gum 
of  the  European  black  poplar  and  of  our  American  balsam  poplar 
has  often  been  employed  by  herbahsts  for  various  medicinal  pur- 
poses although  it  has  httle  virtue. 

There  are  in  all  about  twenty-five  existing  species  of  poplar,  of 
which  half  are  found  in  North  America.  Among  these  the  ones 
known  as  aspens  have  an  especially  wide  range,  particularly  the 
quaking  aspen,  Populus  tremuloides,  which  covers  112°  of  longi- 
tude and  41°  of  latitude,  while  the  European  aspen  (Populus  trem- 
ula)  covers  140°  of  longitude  and  35°  of  latitude — the  two  together 
nearly  encirchng  the  globe.  They  form  dense  growths  in  the  north 
woods  and  furnish  most  of  the  drift  wood  of  the  Arctic  Ocean. 
Although  cut  in  vast  quantities  for  pulpwood  the  aspens  will 
probably  always  form  an  important  element  in  the  more  northern 
forests  as  they  and  their  ancestors  have  done  during  the  past  three 
or  four  miUion  years.  They  repeat  the  usual  poplar  characters  of 
smooth  bark,  soft  weak  wood,  very  rapid  growth  and  sparse  broad 
leafed  foliage.  They  are  more  gregarious  and  somewhat  smaller 
at  maturity  than  the  other  poplars  and  their  long  slender  leaf 
stalks  cause  the  hghtest  summer  breeze  to  set  the  leaves  to  quaking 


90  TREE   ANCESTORS 

or  trembling  with  the  characteristic  motion  and  sound  that  gives 
them  their  vernacular  names.  This  gave  rise  to  the  tradition  that 
aspen  was  the  wood  of  the  cross — its  leaves  have  quivered  ever 
since.  Other  interesting  poplars  are  the  so-called  cottonwoods  of 
the  West,  where  they  are  almost  the  only  native  trees  in  the  river 
valleys  of  the  prairie  country,  ranging  from  Assiniboia  to  New 
Mexico.  The  cottonwood  has  narrower  leaves  than  the  rest  of 
the  poplars  and  in  the  commonest  species  it  approaches  a  willow 
leaf  in  appearance. 

Neither  ^villow  nor  poplar  timber  can  compete  with  larger  and 
stronger  woods  such  as  pine  or  spruce  or  with  more  durable  woods 
such  as  oak,  cedar,  and  chestnut.  Pulpwood,  excelsior,  and  fuel 
are  their  largest  uses  although  for  bam  floors,  boxboard  veneer, 
spools,  matches,  etc.,  their  qualities  of  softness,  lightness,  ease  of 
working  and  lack  of  splintering,  render  them  valuable. 

The  geological  history  of  the  poplars  is  most  interesting  although 
somewhat  obscure.  About  125  fossil  forms  have  been  described, 
in  addition  to  the  still  existing  species  that  are  found  fossil  in  the 
Pleistocene  deposits  but  a  number  of  these  are  of  questionable 
identity.  The  oldest  known  were  the  contemporaries  of  the  dino- 
saurs of  the  closing  days  of  the  Lower  Cretaceous.  One  small 
leafed  form  is  found  at  this  early  day  in  the  Potomac  River  valley 
and  the  other,  which  was  for  a  long  time  the  oldest  known  dicotyle- 
don, comes  from  the  Kome  beds  of  western  Greenland  and  was 
named  Populus  primaeva  by  Heer,  its  describer. 

These  first  poplars  are  rare  forms  but  their  geographical  separa- 
tion gives  us  a  hint  that  their  abundance  was  greater  in  those  early 
days  than  the  records  show,  and  this  is  also  indicated  by  the  abun- 
dance and  wide  distribution  of  poplars  during  the  Upper  Cretaceous, 
from  which  about  30  species  have  been  described.  They  are  much 
less  abundant  than  the  willows  in  the  Upper  Cretaceous  of  Europe 
but,  unlike  the  willows,  they  are  common  in  Greenland,  and  they 
are  exceedingly  ubiquitous  in  North  America  at  this  time,  especially  . 
in  the  West  where  they  appear  to  have  been  very  common  along 
the  borders  of  the  Upper  Cretaceous  sea  that  submerged  so  much 
of  the  then  low  western  country.     In  addition  to  the  American^ 


THE  WILLOWS  AND  POPLARS  91 

European  and  Arctic  records  a  petrified  piece  of  a  poplar  root  has 
been  described  from  the  Upper  Cretaceous  of  Japan,  indicating 
that  Asia  had  its  species  then  as  now.^ 

During  the  succeeding  Eocene  period  there  were  upwards  of 
50  species,  or  twice  as  many  as  are  living  at  the  present  time. 
The  rising  land  of  what  is  now  the  Rocky  Mountain  country 
shut  off  the  moisture  laden  winds  from  the  Pacific  and  the  lessen- 
ing rainfall  made  of  this  vast  region  a  quite  different  country  from 
what  it  had  been  during  the  Upper  Cretaceous.  In  the  continental 
deposits  of  the  Eocene,  that  is,  deposits  laid  down  on  the  bosom 
of  the  land  rather  than  in  the  sea— the  deposits  of  wind  blown 
materials  and  volcanic  dust,  laid  down  in  lakes,  streams,  flood- 
plains,  etc. — deposits  referred  to  the  Fort  Union  formation,  leaves 
of  poplars  are  the  most  abundant  fossils. 

Poplars  appear  to  have  covered  at  this  time  all  of  the  plains  and 
mountain  country  of  the  West  in  great  variety,  extending  north- 
ward from  the  western  provinces  of  the  United  States  and  Canada 
to  Alaska  and  the  mouth  of  the  Mackenzie  River,  and  encircling 
the  globe  in  high  latitudes.  They  have  been  recorded  from  Green- . 
land,  Grinnell  Land,  Spitzbergen,  Sachalin,  Siberia  and  Manchuria. 
A  few  are  found  in  central  Europe,  but  the  great  bulk  are  American 
and  Arctic,  and  the  climate  of  more  southern  lands  appears  to  have 
been  too  warm  for  their  presence  in  any  great  numbers,  for  in  the 
abundant  Eocene  floras  of  southeastern  North  America  we  find  no 
traces  of  poplars  but  in  their  place  a  warm  climate  flora  of  figs, 
laurels,  bread  fruit,  rain  trees  and  their  allies,  thatch  and  date 
palms,  nutmegs,'  pond  apples  and  similar  types  unfamihar  to 
dwellers  in  the  Temperate  Zone.  This  warm  flora  extends  as  far 
north  as  the  mouth  of  the  Ohio  in  America  and  a  similar  warm 
flora  extends  to  southern  England  in  Europe. 

During  the  Ohgocene,  which  succeeded  the  Eocene,  the  scanty 
records  have  yielded  few  poplars.  Three  species  have  been  de- 
scribed from  deposits  of  this   age  in   the  West   and  4   or  5    are 

^  Many  of  these  early  poplars  are  thought  by  some  students  to  represent  an 
altogether  different  family  of  plants — the  Trochodendraceae. 


92  TREE   ANCESTORS 

known  from  central  and  southern  Europe.  Southeastern  North 
America  was  still  too  tropical  in  its  climate  to  permit  the  existence 
of  poplars  and  although  we  lack  the  proof  it  may  be  assumed  that 
the  numerous  Eocene  forms  lived  on  in  Arctic  lands  until  they  were 
gradually  exterminated  or  driven  southward  by  the  more  severe 
climate  that  commenced  to  prevail  in  high  latitudes  before  the 
close  of  the  OHgocene. 

The  poplars  are  represented  during  the  Miocene  period  by  about 
30  species,  which  are  found  from  Greece  westward  to  Spain  in 
Europe  and  throughout  the  western  United  States  and  Canada. 
The  Miocene  lake  of  Florissant  in  the  heart  of  the  Colorado  Rockies 
has  furnished  7  forms  of  poplar — one  a  splendidly  preserved 
Cottonwood  that  may  well  have  been  the  ancestor  of  the  existing 
forms  that  are  found  at  the  present  time  in  Colorado.  Poplars 
are  found  at  this  time  along  the  Pacific  coast,  but  none  are  known 
from  the  Atlantic  or  Gulf  coasts. 

The  Pliocene  period,  which  succeeded  the  Miocene  and  immedi- 
ately preceded  the  Glacial  period,  has  furnished  about  16  species 

Fig.  18.  Some   Fossil  Willows   and   Poplars   (About  |  Natural  Size) 

1.  Leaf;  2,  fruit  of  Salix  varians  Goeppert  from  the  Miocene  (Tortonian)  of 
Switzerland. 

3.  Salix  lavateri  Heer  from  the  Miocene  (Tortonian)  of  Baden. 

4.  Salix  angusta  Al.  Braun  from  the  Miocene  (Tortonian)  of  Baden. 

5.  Staminate  catkin  of  Salix  from  the  Miocene  (Tortonian)  of  Silesia. 

6.  Salix  reticulata  Linne  from  the  Pleistocene  of  Germany. 

7.  Salix  herhacca  Linne  from  the  Pleistocene  of  Galicia. 

8.  Salix  polaris  Wahl.,  from  the  Pleistocene  of  England. 

9.  Salix  myrtilloidcs  Linne  from  the  Interglacial  of  England. 

10.  Leaf;  11,  bracts;  12,  fruit  of  Populus  latior  Al.  Braun  from  the  Miocene 
(Tortonian)  of  Baden. 

13.  Populus  crassa  (Lesq.)  Ckl.,  from  the  Miocene  of  Florissant,  Colorado. 

14.  Populus  balsamoidcs  Goeppert  from  the  Miocene  (Tortonian)  of  Silesia. 

15.  Populus  aniblyrhyncha  Ward  from  the  Eocene  (Fort  Union)  of  Montana. 

16.  Populus  heliadum  Unger  from  the  Miocene  (Tortonian  )  of  Baden. 

17.  Populus  attenuata  Al.  Braun  from  the  Miocene  (Tortonian)  of  Baden. 

18.  Catkins;  19,  leaf;  20,  scales;  21,  leafy  twig  of  Populus  mutahilis  Heer  from 
the  Miocene  (Tortonian)  of  Baden. 

22.  Populus  halsamijera  Linne  from  the  late  Pleistocene  of  Maine. 


THE   WILLOWS    AND   POPLARS 


93 


Fig.  18 


94  TREE   ANCESTORS 

of  poplars,  several  of  which  are  very  close  to,  if  not  identical  with, 
still  existing  European  forms  such  as  the  European  aspen,  the 
silver  poplar  and  its  downy  leafed  ally.  They  are  found  during 
this  period  from  Asia  Minor  to  Spain,  but  there  are  no  known  Ameri- 
can records,  since  tliis  country  has  unfortunately  yielded  scarcely 
any  Pliocene  plants. 

The  Pleistocene  or  Glacial  period  is  always  of  particular  interest 
to  students  of  plant  history  and  distribution  since  the  presence  of 
continental  ice  sheets  and  the  complex  physical  conditions  which 
their  presence  brought  about  played  havoc  with  the  uniformity 
of  development  and  distribution  of  the  noble  races  of  both  animals 
and  plants  that  had  been  flourishing  for  so  many  thousands  of 
years  throughout  the  Northern  Hemisphere. 

Poplars  are  represented  in  the  Pleistocene  deposits  of  Europe 
and  America  by  wood,  leaves,  bud-scales  and  catkins.  Only  2 
of  the  10  species  recorded  from  these  deposits  are  extinct  and 
these  are  both  from  the  earlier  Pleistocene  of  Maryland  and  are 
very  similar  to  existing  forms.  In  Europe  the  black  poplar  is 
recorded  from  Italy;  the  downy  white  poplar  has  been  found  in 
both  England  and  France;  and  the  European  quaking  aspen  occurs 
in  peat  deposits  at  a  number  of  localities  in  Denmark,  Germany, 
northern  Italy,  etc.  In  America  the  so-called  necklace  poplar 
{Populus  deltoides)  has  been  found  in  river  terrace  deposits  in 
Alabama  and  western  Kentucky,  and  the  balsam  poplar  or  Tacama- 
hac,  and  the  large  toothed  aspen,  have  been  found  in  the  Interglacial 
beds  of  the  Don  Valley  in  Ontario,  and  the  former  has  also  been 
found  in  the  blue  clays  of  Maine. 

Thus  we  see  that  while  the  life  span  of  both  willows  and  poplars 
is  much  shorter  than  that  of  most  of  our  forest  trees,  the  stock  is  a 
virile  one  and  the  race  an  ancient  one.  While  neither  have  been 
objects  of  veneration  or  worship  like  the  oaks  or  ginkgoes,  or  of 
surpassing  utility  like  so  many  of  our  forest  trees,  both  were  the 
associates  of  our  remote  ancestors  of  the  Old  Stone  Age  when  the 
last  ice  sheets  were  retreating  from  northern  Europe  and  the  Nor- 
dic race  was  being  evolved.  Both  willows  and  poplars  must  have 
been  familiar  and  useful  plants  to  the  Neolithic  men  that  evolved 


THE  WILLOWS  AND  POPLARS  95 

the  so-called  Robenhausian  culture  of  the  Swiss  lake  dwellers 
(7000-5000  B.C.),  the  remains  of  whose  dwellings,  built  on  piles 
and  found  so  abundantly  throughout  the  region  of  the  Alps  and 
the  valley  of  the  Danube,  record  the  time  when  early  man  ceased 
being  merely  a  nomadic  hunter  and  came  to  occupy  fixed  abodes 
and  garnered  some  crops.  And  when  the  race  passed  from  lake 
dwellings  to  fortified  and  moated  habitations  in  the  swamps  and 
along  the  rivers  of  southern  Europe,  the  willows  must  have  been 
one  of  the  familiar  and  useful  plants  in  their  immediate  environ- 
ment, during  what  is  called  the  Terramara  period,  so  that  they  should 
have  at  least  a  sentimental  interest  for  the  modern  race.  Unlike 
more  useful  trees  to  the  lumber  industry  the  willows  and  poplars, 
because  of  their  efficient  seeding  habits  and  rapid  growth,  do  not 
appear  to  be  in  danger  of  extermination,  despite  the  enormous 
toll  that  the  pulp  mills  and  forest  fires  take  every  year. 


CHAPTER  XI 

Hornbeam,  Hazel,  Birch  and  Alder 

The  various  hornbeams,  hazels,  birches  and  alders  belong  to 
the  birch  family  or  Betulaceae,  which  is  a  most  important  one  from 
both  the  aesthetic  and  pragmatic  points  of  view.  Its  numerous 
species  are  segregated  into  6  main  groups  or  genera,  all  of  which 
have  many  common  features  of  wood,  leaf,  and  flower  structure. 
The  most  uninformed  are  familiar  with  some  of  the  birches,  alders, 
hazels  and  hornbeams — the  hop  hornbeam  (Ostrya)  is  less  well 
known,  leaving  the  genus  Ostryopsis  with  a  single  species  in  eastern 
Asia  as  the  sole  practically  unknown  member  of  the  family. 

All  of  the  genera  except  the  last  mentioned  have  numerous 
species  found  in  all  the  northern  continents,  and  all  these  have 
numerous  extinct  representatives.  The  only  member  of  the  family 
that  extends  its  range  into  the  Southern  Hemisphere  is  the  alder 
(Alnus)  which  has  spread  southward  through  the  highlands  of 
Mexico  and  Central  America  to  the  Andes  of  Peru  and  Bolivia 
where  it  is  associated  with  familiar  looking  trumpet  creepers  and 
blackberries.  It  will  be  more  illuminating  to  briefly  discuss  each 
of  the  types  mentioned  at  the  head  of  this  chapter  separately. 

THE  birch,  "the  LADY  OE  THE  WOODS" 

In  considering  the  birches  the  aesthetic  and  the  practical  both 
struggle  for  a  hearing.  Our  northern  forests  are  not  adorned  with 
more  beautiful  or  graceful  trees  than  the  white  or  silver  birches, 
and  in  some  countries  such  as  Russia  and  Kamchatka  this  lady  of 
the  woods  becomes  a  maid  of  all  work  and  serves  as  many  purposes 
as  does  the  palm  in  Arabia.  Poets  generally,  unite  in  its  praises, 
but  on  the  other  hand  Evelyn  has  not  a  word  for  the  beauty  of  the 
birch  but  praises  the  sovereign  efi'ects  of  its  juice  when  made  into 
birch  beer. 

96 


HORNBEAM,   HAZEL,    BIRCH    AND    ALDER  97 

The  birches  constitute  the  genus  Betula,  which  was  the  classical 
name  of  the  European  tree.  It  is  the  largest  genus  and  gives  its 
name  to  the  family.  There  are  about  30  existing  birches  recognized 
by  botanists  and  over  four  times  as  many  extinct  species.  They 
range  in  size  from  tiny  shrubs  under  the  Arctic  Circle,  for  they 
extend  as  far  north  as  any  tree  genus,  to  trees  125  feet  tall  in  the 
case  of  our  northwestern  birch  {Betula  occidentalis) ,  and  some,  like 
our  American  white  birch  {Betula  populifolia)  may  be  in  the  far 
north  or  on  mountains  only  2  or  3  feet  tall  as  compared  w^ith  a 
height  of  40  feet  in  more  favorable  situations.  Most  of  the  birches 
are  relatively  short  lived  and  slender  trees,  of  slow  growth,  but 
hardy  and  freely  seeded  by  the  wind,  with  round  slender,  often 
drooping  branches,  serrate  toothed  deciduous  leaves  of  a  bright 
green  color,  with  the  pollen  and  seed  producing  catkins  in  separate 
clusters  but  borne  on  the  same  tree,  and  producing  tiny  winged 
fruits.  The  bark  is  one  of  their  characteristic  features,  being  in 
thin  layers  and  readily  peeled  off,  and  quite  indestructible. 

The  accompanying  map  will  explain  their  distribution  much  more 
grapliically  than  many  words.  The  dwarf  Arctic  birches  of  the 
Pleistocene  and  recent  barren  grounds  or  tundra  reach  to  within 
ten  degrees  of  the  North  Pole  in  western  Spitzbergen,  and  almost 
as  far  on  the  coasts  of  Greenland.  The  white  birches  extend  north- 
ward beyond  the  Arctic  Circle  in  Scandinavia,  Siberia,  Alaska  and 
the  valley  of  the  Mackenzie,  and  reach  their  southern  limits  in 
Spain,  Asia  Minor,  Japan  and  California.  The  remaining  birches 
occupy  large  detached  areas,  the  smallest  being  that  of  the  Caucasus 
and  Armenia.  In  Asia  these  forms  cover  a  large  area  extending 
from  eastern  Siberia  southwestward  to  the  Vale  of  Kashmir;  in 
North  America  they  extend  from  the  St.  Lawrence  valley  westward 
to  Minnesota  and  southward  to  eastern  Texas  and  Florida. 

Their  twigs  are  still  used  extensively  in  the  manufacture  of 
brooms  just  as  in  ancient  Rome  the  fasces  of  the  Hctors  with  which 
they  cleared  the  way  for  the  magistrates,  were  made  of  birch 
rods.  Their  use  among  pedagogues  was  so  general  in  northern 
Europe  and  New  England  that  birch  is  still  literally  or  more  often 
metaphorically    the    instrument    of    school    room    discipline.     In 


98  TREE    ANCESTORS 

America  the  birch  has  all  the  attendant  romance  that  clusters 
about  the  birch  bark  canoes  of  the  aborigines  and  early  traders 
and  trappers,  and  they  are  still  indispensable  in  the  North  woods. 
Tliis  is  strikingly  set  forth  in  the  eighteenth  century  journal  of 
Alexander  Mackenzie  on  his  journey  from  Montreal  to  the  Pacific. 
He  relates  how  he  hunted  whales  in  a  birch  canoe  in  the  estuary  of 
the  river  which  bears  his  name  and  how  he  carried  such  a  canoe 
across  the  Rocky  Mountains,  at  least  during  the  intervals  when 
the  canoe  was  not  carrying  him — probably  the  first  white  man  to 
make  such  a  journey. 

Living  in  cities  as  most  of  us  have  the  misfortune  to  do  in  these 
modern  days,  we  scarcely  realize  the  number  and  variety  of  uses 
to  which  our  common  trees  are  put  in  remote  parts  of  the  world 
away  from  the  beaten  tracks.  We  are  not  quite  so  uninformed  as 
the  slum  children  who  think  that  apples  grow  in  barrels  and  peaches 
in  baskets,  but  what  city  dweller  would  dream  that  some  thirty 
million  spoons  were  each  year  made  out  of  birch  wood  in  Russia, 
or  that  the  Russian  peasants  use  about  twenty-five  miUion  pairs 
of  birch  bark  shoes  annually,  or  that  Kamchatkans  grind  up  the 
bark  and  eat  it  for  the  contained  starch,  or  that  considerable 
mahogany  furniture  in  the  antique  shops  is  of  sweet  birch,  or  that 
eleven  thousand  cords  of  papqr  birch  are  used  each  year  in  New 
England  in  the  manufacture  of  shoe  pegs.  One  would  be  inclined 
to  think  that  shoe  pegs  were  as  obsolete  as  distaffs  or  flails,  but 
such  is  not  the  case. 

Our  paper  birch  {Betula  papyrifera) ,  also  often  called  the  canoe 
birch,  extends  through  our  northern  tier  of  States  almost  from  the 
Atlantic  to  the  Pacific  and  reaches  northward  almost  to  the  shores 
of  the  Arctic.  It  is  one  of  the  few  American  trees  that  covers 
more  ground  at  the  present  time  than  it  did  when  America  was 
discovered.  It  owes  its  spread  to  the  success  with  which  it  col- 
onizes spaces  that  have  been  opened  in  the  forests  by  windfalls  or 
fires.  Its  light  winged  fruits  are  produced  in  great  quantities  and 
are  carried  far  and  wide  by  the  winds — they  may  often  be  seen 
as  tiny  bird-like  specks  on  the  surface  of  winters  snows.  A  similar 
habit  of  rapidly  spreading  over  clearings  and  waste  places  character- 


HORNBEAM,   HAZEL,    BIRCH   AND    ALDER 


99 


izes  the  European  white  or  silver  birch^a  closely  related  but  dis- 
tinct species — which  is  one  of  the  few  trees  that  grows  among  the 
heather,  in  fact  an  abundance  of  seeds  widely  distributed  by  the 
wind  characterizes  most  of  the  birches  and  is  especially  noticeable 
in  the  changing  cycles  of  vegetation  recorded  in  Pleistocene  de- 
posits which  contain  the  history  of  bogs  and  moors  changing  into 
forests  and  back  again. 


Fig.  19.  Sketch  Map  Sho\ving  Ancient  and  Modern  Distribution 
or  the  Birches 

Northern  limits  of  Arctic  birches. 

Northern  and  southern  limits  of  white  birches. 

X  X  X  X  X  X  Range  of  other  birches  (subsections  Costatae  and  Betulaster). 
•  •  #  •  Fossil  occurrences. 


A  most  thrilling  story  could  be  written  of  the  part  played  by 
the  birch  bark  canoe  in  the  exploration  and  development  of  the 
northern  half  of  our  continent,  Parkman  gives  something  of  this. 


100  TREE   ANCESTORS 

We  owe  the  discovery  of  the  Mississippi  to  its  use,  and  it  would  be 
a  safe  assertion  that  the  settlement  of  much  of  this  country  with 
its  intricate  systems  of  rivers  and  lakes  would  otherwise  have  been 
impossible.  In  Hiawatha  we  read  the  mythical  account  of  the 
first  birchbark  canoe  and  Longfellow  there  describes  the  actual 
process  of  building  with  accuracy.  Bark  canoes  are  still  made  in 
the  backwoods  by  trappers  and  Indians,  and  around  some  of  the 
lake  resorts,  and  the  wood  because  of  the  inherited  tradition  as 
well  as  because  of  its  intrinsic  worth  is  similarly  used  by  canoe  and 
small  boat  manufacturers. 

For  the  manifold  uses  of  birch  wood  of  the  various  species  I 
must  refer  the  reader  to  the  special  literature  of  forestry — that  half 
a  billion  board  feet  are  cut  by  saw  mills  in  the  United  States  each 
year  is  an  index  of  its  commercial  position.  For  two  centuries, 
and  from  Maine  to  Tennessee,  much  of  the  finest  birch  disappeared 
before  the  pioneer's  axe  without  any  realization  of  its  value  other 
than  for  fuel.  Our  most  valuable  commercial  species  is  probably 
the  sweet  or  cherry  birch  {Betula  lento)  although  the  various  species 
are  often  indiscriminately  mixed  in  lumbering.  Indians  from  time 
immemorable  have  made  birch  beer  by  fermenting  its  sugary  sap, 
which  is  copious.  Inhabitants  throughout  its  range  still  utiHze 
the  sap  in  this  way,  although  birch  beer  can  scarcely  be  said  to  be 
an  article  of  commerce.  The  sweet  birch  was  also  the  first  of  the 
birches  whose  value  was  recognized,  and  the  wood  was  exported 
to  Britain  as  early  as  1791.  It  enters  largely  into  cabinet  and 
furniture  making,  into  musical  instruments,  interior  finish,  boats, 
bilHard  cues,  mallets,  Indian  clubs,  wooden  ware,  and  from  the 
time  of  the  first  cabinet  makers  it  has  been  a  substitute  for  cherry 
or  mahogany — and  a  most  admirable  one. 

CXir  other  birches,  aside  from  the  uses  of  the  bark  of  the  paper 
birch,  were  not  recognized  as  valuable  until  much  later,  although 
the  yellow  birch  {Betula  lutea)  has  been  an  article  of  commerce  for 
over  one  hundred  years,  going  into  wooden  ware,  furniture,  ve- 
hicles, etc.  The  paper  birch  goes  into  clothes  pins,  toothpicks, 
woodenware,  novelties  and  cooperage — its  largest  use  being  prob- 
ably the  result  of  the  possession  of  the  exacting  quahties  required 


HORNBEAM,    HAZEL,    BIRCH    AND    ALDER  101 

in  modern  winding  machines  of  spools.  All  of  our  birches  enter 
more  or  less  into  wooden  ware,  novelty  and  furniture  trades.  In 
Maryland  the  common  river  birch  (Betula  nigra)  with  wood  of 
modest  merit  goes  extensively  into  berry  baskets. 

For  the  past  sixty  years  the  distillation  of  sweet  birch  bark  has 
furnished  an  oil  so  similar  to  that  of  the  true  oil  of  wintergreen, 
that  it  has  almost  entirely  superseded  the  latter  where  this  flavoring 
is  required.  Dry  distillation  furnishes  the  oil  used  in  tanning 
Russian  leather  and  to  which  the  latter  owes  its  pleasant  odor. 
In  frontier  regions  the  bark  of  various  species  furnishes  a  substitute 
for  paper,  and  is  used  more  extensively  for  roofing  and  for  jars  and 
containers — alike  by  the  American  Indian  for  his  maple  sugar  and 
by  the  Russian  peasant  for  both  liquids  and  solids.  There  are 
great  tracts  of  birch  in  Russia  where  this  tree  is  close  to  the  daily  4 
life  of  the  masses  and  where  its  leaves  are  frequently  used  for 
fodder. 

The  birches  play  a  considerable  part  in  geological  history.  As 
I  mentioned  in  an  earlier  paragraph  there  are  about  135  extinct 
species — the  earliest  known  birch-like  forms  being  referred  to  a 
genus  known  as  Betulites,  of  which  a  score  of  species  and  varieties 
were  described  by  Lesquereux  from  the  Dakota  sandstone  of 
Kansas,  in  which  they  are  present  in  large  numbers.  Supposedly 
similar  forms  have  been  recorded  from  the  Upper  Cretaceous  of 
Argentina,  but  these  have  never  been  passed  upon  by  a  competent 
botanist  and  remain  doubtful,  although  the  presence  of  what  Dusen 
calls  Betuliphyilum  in  the  early  Tertiary  of  the  Straits  of  Magellan, 
lends  some  support  to  the  idea  that  the  ancestral  birch  stock  may 
have  reached  South  America  from  the  North  during  the  Upper 
Cretaceous.  But  if  it  did  it  entirely  failed  to  secure  a  lasting  foot- 
hold on  that  continent. 

Other  Upper  Cretaceous  birches,  referred  directly  to  the  modern 
genus,  number  5  or  6  and  come  from  western  Greenland,  Ne- 
braska, and  western  Canada,  wood  as  well  as  leaves  being  recorded 
from  the  last  region.  Birches  are  unknown  in  the  European  Cre- 
taceous, but  that  they  reached  that  continent  early,  either  from 
Asia  or  from  the  Arctic  by  way  of  a  North  Atlantic  land  bridge, 


102  TREE    ANCESTORS 

is  shown  by  their  presence  in  the  lowermost  (oldest)  Eocene  of  the 
Paris  basin. 

Birches  are  a  widespread  and  common  type  in  the  Eocene  floras, 
occurring  in  the  earliest  rocks  of  this  age  in  both  Europe  and  Amer- 
ica. About  30  Eocene  species  have  been  described,  and  during  the 
northward  swing  of  temperate  forests  which  is  one  of  the  most 
spectacular  events  of  Eocene  times,  birches  penetrated  almost  to 
the  pole  itself,  in  Spitzbergen,  Banks  Land,  Grinnell  Land,  Green- 
land and  Iceland,  in  addition  to  being  exceedingly  abundant  on 
all  the  northern  continents,  especially  in  Alaska  and  the  western 
provinces  of  Canada.  At  this  time  they  are  supposed  to  have 
reached  Austraha  and  Tasmania,  but  these  antipodal  occurrences 
are  not  above  suspicion  and  may  merely  represent  incorrect  de- 
terminations. In  the  region  of  the  not  yet  elevated  Rocky  moun- 
tains was  an  area  still  swept  by  humid  Pacific  winds,  the  dwelHng 
place  of  several  typical  species  of  birch  whose  foliage  doubtless 
helped  to  furnish  the  fare  of  the  early  browsing  mammals,  not  yet 
learned  in  the  habit  of  grazing. 

The  Oligocene  records  include  some  ten  or  a  dozen  species, 
almost  entirely  European  for  reasons  explained  in  connection  with 
the  history  of  other  trees,  and  their  remains  are  beautifully  pre- 
served in  the  Baltic  amber,  as  well  as  in  the  gypsiferous  shales  of 
southeastern  France.  During  succeeding  Miocene  times  the 
birches  reached  the  acme  of  their  development.  Over  40  Miocene 
species  are  known,  and  they  left  their  remains  in  the  deposits  of 
this  time  on  all  the  larger  land  masses  of  the  Northern  Hemisphere 
from  Japan  westward  to  France,  and  in  Colorado,  Oregon  and 
Cahfornia,  being  especially  abundant  throughout  southern  Europe. 
They  continued  in  but  slightly  abated  abundance  in  the  last  named 
region  throughout  the  Phocene,  and  a  species  named  prenigra  since 
it  appears  to  be  ancestral  to  the  modem  American  river  birch,  has 
been  found  in  the  Phocene  deposits  formed  at  that  time  along  the 
then  Gulf  coast  in  Alabama. 

Birches  were  unusually  numerous  during  the  Pleistocene,  about  a 
dozen  species  having  been  recorded,  largely  because  they  dwelt  in 
regions  where  their  remains  could  take  a  part  in  the  numerous  peat 


HORNBEAM,   HAZEL,   BIRCH   AND   ALDER  103 

bogs  that  were  formed  at  that  time.  Most  of  the  Pleistocene  birches 
represent  still  existing  species.  At  this  time  the  dwarf  arctic 
birch  {Betula  nana)  retreated  southward  before  the  advancing  ice 
sheets  and  left  its  remains  in  England,  Scotland,  Germany  and 
Galicia.  The  European  white  birch  {Betula  alba)  has  been  found 
fossil  in  Scotland,  Hebrides,  Skye,  Germany,  Italy  and  Japan. 
Other  fossil  species  occur  in  Germany,  Galicia,  Japan  and  Hungary. 
In  North  America  the  yellow  birch  (Betula  lutea)  has  been  found 
fossil  in  Ontario;  the  river  birch  {Betula  nigra)  has  been  found  in 
Virginia,  West  Virginia,  Kentucky,  North  Carolina,  Alabama, 
and  Mississippi;  and  other  species  occur  in  North  CaroHna  and 
Kentucky. 

THE    HAZEL 

"Hazel  buds  with  crimson  gems, 
Green  and  glossy  sallows." 

The  hazel  was  one  of  Thor's  trees,  and  together  with  the  witch 
or  wych  elm  {Ulmus  montana),  was  an  object  of  considerable  ven- 
eration among  the  Saxons.  The  name  witch  hazel  appHed  to  the 
hazel  by  Nordic  peoples,  and  not  to  be  confused  with  the  true  witch 
hazel  of  America  which  belongs  to  an  altogether  different  tree 
family,  is  said  to  have  been  derived  from  the  Anglo  Saxon  wic-en 
to  bend,  although  the  fact  that  hazel  twigs  were  commonly  used 
as  divining  rods  suggests  that  the  tree  had  long  been  associated 
with  magic. 

The  scientific  name  of  the  genus,  Corylus,  is  derived  from  the 
Greek,  and  is  in  allusion  to  the  helmet-Hke  leafy  envelope  which 
in  the  nut  bearing  flower  enlarges  and  surrounds  the  nut,  or  grows 
out  around  it  into  a  tubular  beak.  There  are  about  8  existing 
species  and  22  varieties  recognized  by  botanists  and  many  of  the 
latter  are  often  raised  to  the  rank  of  species.  Of  these  Eurasia 
has  6  species  and  20  varieties,  and  North  America  3  species  and 
1  variety — one  of  the  American  species  {calijornica)  of  Washing- 
ton, Oregon  and  CaUfornia  being  frequently  considered  as  simply 
a  variety  of  Corylus  rostrata,  our  beaked  hazel  nut,  along  with 
4   other  varieties  (or  species)  of  Manchuria,  Korea,  Japan  and 


104 


TREE   ANCESTORS 


China,  which  at  least  illustrates  the  community  of  origin  of  many 
of  the  trees  of  North  America  and  eastern  Asia. 

The  hazels  are  all  shrubs  or  small  trees,  especially  toward  their 
northern  limits,  although  the  beaked  hazel  frequently  reaches 
heights  of  between  15  and  20  feet  north  of  the  Great  Lakes.  Com- 
monly, even  as  far  south  as  southern  New  England,  the  hazels  are 
shrubs  of  rocky  thickets  or  fence  rows,  seldom  attaining  the  stature 


Fig.  20.  Existing  Range  and  Fossil  Occurrences  of  the  Hazel  Outside 
THE  Modern  Range 


of  small  trees,  although  some  of  the  foreign  species  are  somewhat 
larger.  Their  wood  is  of  no  commercial  importance,  although 
that  of  the  western  species  is  sometimes  used  for  broom  handles. 
Nor  are  the  nuts  much  sought  after,  though  this  is  not  the  case 
abroad  where  hazels  are  the  chief  quest  of  youthful  nutting  expedi- 
tions during  the  fall  of  the  year,  and  we  import  a  considerable 
quantity  of  hazel  nuts  under  the  name  of  filberts. 


HORNBEAM,   HAZEL,    BIRCH   AND   ALDER  105 

Hazel  leaves  are  broadly  ovate,  with  sharply  pointed  tips  and 
truncate  or  heart  shaped  bases.  The  margins  are  finely  toothed  and 
may  be  in  addition  cut  into  small  segments,  suggestive  of  the  leaves 
of  the  white  birch,  but  coarser  and  of  a  different  shade  of  green. 
The  leaves  of  all  the  species  have  a  great  mutual  resemblance 
and  show  considerable  variability,  so  that  it  becomes  exceedingly 
difiicult  to  discriminate  the  fossil  species,  which  consequently  have 
been  multiplied  beyond  all  reason. 

Scarcely  any  of  our  trees  are  more  interesting  in  that  hazel 
leaves  are  very  common  as  fossils  in  northern  lands  beyond  their 
present  limits,  and  have  the  distinction  of  having  been  found  to 
within  10°  or  12°  of  the  pole,  being  consequently  of  much  impor- 
tance in  attempts  to  picture  Tertiary  geological  climates. 

Conservatively  treated  the  number  of  extinct  kinds  of  hazel 
considerably  exceeds  the  living  varieties,  and  the  more  spectacular 
time  in  their  history  was  at  the  time  of  their  earliest  appearance 
in  the  geological  record.  This  was  during  the  early  Tertiary,  for 
none  are  known  from  the  Upper  Cretaceous.  About  10  species 
are  known  from  this  early  Tertiary  or  Eocene  time,  and  2  of  these, 
found  in  the  wooded  region  that  at  that  time  covered  our  prairie 
country  in  western  Canada,  the  Dakotas,  Montana,  etc.,  are  so 
Hke  our  two  existing  Atlantic  species  that  their  leaves  are  scarcely 
to  be  distinguished  and  have  frequently  gone  by  the  same  names, 
although  of  course  no  tree  species  has  continued  unaltered  through 
such  a  vast  lapse  of  time  as  that  separating  the  Eocene  from  the 
present. 

But  the  chief  interest  of  the  Eocene  hazels  is  their  northern 
range.  They  were  exceedingly  abundant  at  that  time  in  the  far 
northern  parts  of  all  the  continents  of  the  Northern  Hemisphere. 
At  least  3  species  and  many  varieties  are  found  in  Alaska,  where 
their  leaves  are  among  the  commonest  of  fossils.  If  the  Macken- 
zie River  existed  in  those  far  off  days,  hazel  thickets  hned  its  bank 
where  it  emptied  into  the  Arctic  Ocean  since  their  fossil  remains 
are  common  in  the  shales  near  its  mouth.  Hazels  were  equally 
common  in  western  Greenland  and  between  the  early  Tertiary 
lava  flows  on  the  Island  of  Mull,  and  in  Siberia.     Still  farther  north 


106  TREE   ANCESTORS 

their  leaves  are  found  in  Spitzbergen,  and  at  the  farthest  northern 
outpost  to  which  temperate  forests  are  known  to  have  penetrated 
at  that  or  any  other  time,  namely,  to  within  10°  of  the  pole  itself 
in  Grinnell  Land,  where  two  kinds  of  hazel  are  preserved  in  rocks 
that  are  today  covered  with  perpetual  snow  and  ice. 

These  Eocene  records  are  found  in  a  belt  between  40°  and  80° 
north  latitude,  and  south  of  that  belt  are  found  traces  of  a  warmer 
temperate  flora — that  from  the  shores  of  the  Mississippi  Gulf  of 
that  time  being  sub-tropical.  In  the  present  flora  of  Spitzbergen, 
among  the  130  species  of  knowoi  flowering  plants,  there  is  only  a 
single  tree  genus — Salix,  the  willow — there  only  2  or  3  inches  tall. 
The  hazel  today  ranges  from  about  31°  north  (northern  Florida) 
to  55°  in  North  America  and  to  about  60°  in  southern  Sweden. 
The  Middle  Eocene  was  a  time  of  expanded  seas  and  partially 
submerged  continents,  and  it  is  believed  that  the  resulting  free 
circulation  of  the  warm  ocean  waters  so  ameliorated  the  chmate 
that  the  tropics  spread  into  the  present  temperate  zones  and  the 
temperate  zones  spread  far  toward  both  poles,  without  any  sharp 
contrasts  except  in  the  interior  of  the  land  masses.  This  was  the 
time  of  the  mildest  and  most  equable  climates  known  during  the 
whole  Tertiary  period,  but  it  was  far  from  being  absolutely  uni- 
form, or  from  being  tropical  in  the  far  north  as  some  rash  students 
have  asserted.  At  the  present  time  the  warm  drift  of  the  North 
Atlantic  greatly  modifies  the  climate  of  Spitzbergen,  causing  the 
isotherms  to  extend  far  north  of  their  average  position — the  iso- 
therm of  23°  Fahrenheit  reaching  southern  Spitzbergen,  and  the 
present  cold  pole  is  not  at  the  geographical  North  pole,  but  in  the 
severe  continental  climatic  region  of  northern  Siberia. 

Obviously  the  hazel  must  have  originated  in  some  of  these 
northern  lands  where  it  was  so  widely  distributed  and  abundant 
in  those  early  days,  spreading  from  thence  southward  with  the 
changing  climates  of  the  Oligocene,  but  apparently  never  getting 
nearer  the  equator  than  does  our  common  American  hazel  {Corylus 
americana)  or  than  did  Corylus  australis  in  the  Island  of  Madeira 
during  Pleistocene  times. 


HORNBEAM,   HAZEL,   BIRCH   AND   ALDER  107 

During  the  OKgocene,  Miocene  and  Pliocene,  species  of  hazel 
continue  to  be  abundant  on  the  northern  continents,  but  they 
had  retreated  from  the  far  North  and  their  range  is  essentially 
comparable  to  that  of  the  existing  forms.  During  the  Pleistocene 
the  distribution  of  the  common  European  hazel  {Corylus  avellana) 
furnishes  a  valuable  commentary  on  the  shifting  ice  sheets  and  the 
probable  climates  of  the  interglacial  times.  The  remains  of  this 
hazel  in  several  varieties  are  especially  common  in  the  deposits  of 
the  third  interglacial  period  in  northern  Europe,  and  equally 
common  immediately  after  shrinking  of  the  last  ice  sheet.  Thus 
of  224  stations  where  fossil  nuts  have  been  found  in  Sweden,  219 
of  these  are  north  of  the  present  range,  emphatically  proving  that 
the  chmate  has  become  somewhat  more  severe  in  the  last  few 
thousand  years.  An  extinct  Pleistocene  hazel  has  been  described 
from  the  Island  of  Madeira,  and  the  common  American  hazel  has 
been  found  in  cave  deposits  in  Pennsylvania  associated  with  Pleis- 
tocene mammalian  bones. 

THE  HORNBEAM 

Carpinus  was  the  classical  name  of  the  hornbeam,  French  charme. 
Pliny  described  it  and  classed  it  with  the  maples.  The  name  is 
said  to  have  been  derived  from  the  Celtic  car  wood,  and  pin  or 
pen  head,  from  the  early  practise  of  using  the  wood  in  making 
yokes  for  cattle,  in  fact  the  common  European  hornbeam  is  often 
called  yoke  elm. 

The  latter,  which  has  been  much  used  as  an  ornamental  tree  in 
the  northeastern  United  States,  grows  naturally  in  temperate 
western  Asia,  Asia  Minor,  and  in  Europe  northward  to  latitude 
55°.  In  southern  England  it  is  frequently  used  for  hedges  and 
geometrical  planting,  since  it  stands  clipping  well,  as  testified  to  by 
Evelyn,  who  states:  "In  the  single  row  it  makes  the  noblest  and 
stateliest  hedges  for  Long  Walks  in  Gardens  or  Parks,  of  any  tree 
whatsoever  whose  leaves  are  deciduous."  The  wood  is  close 
grained,  tough,  and  hard  to  work,  hence  according  to  Gerard,  its 
name  hornbeam.     It  is  a  common  tree  in  France  where  the  leaves 


108 


TREE    ANCESfORS 


are  frequently  used  for  fodder.  Its  resemblance  to  the  elm  is 
superficial  and  is  based  on  the  leaf  arrangement  and  the  smooth 
greyish  bark. 

The  pollen  bearing  and  seed  bearing  flowers  are  in  separate 
catkins  and  those  of  the  latter,  which  are  lax  and  bracteate,  de- 
velop into  small  ribbed  nutlets  while  the  bracts  are  enlarging  to 
form   the   three   lobed   and  normally  serrately  margined  wings. 


Fig.  21.  Sketch  Map  Showing  the  Existing  Range  and  Fossil 
ocurrences  of  the  hornbeam 


The  hornbeams  are  confined  to  the  Northern  Hemisphere  and  have 
about  a  dozen  existing  species,  found  in  America  from  Quebec  to 
the  Central  American  highlands,  and  in  Eurasia  from  Sweden  to 
southern  Europe,  Asia  Minor,  the  temperate  Himalayas,  central 
China  and  Japan. 

Of  the  dozen  existing  species,  only  one — the  hornbeam  or  blue 
beech,  Carpimis  caroliniana,  is  found  in  North  America.     This  is 


HORNBEAM,   HAZEL,   BIRCH   AND   ALDER  109 

not  a  stately  tree,  rarely  reaching  a  height  of  40  feet,  and  generally 
bushy  in  appearance,  with  a  short  fluted  trunk,  long  slender  irregu- 
larly spreading  branches  and  light  brownish-grey  bark.  It  is  dis- 
tinctly mesophytic  in  habitat  and  most  frequently  found  along 
stream  or  swamp  borders,  and  reaches  its  largest  size  on  the  west- 
em  slopes  of  the  southern  Alleghanies  and  in  Arkansas  and  eastern 
Texas,  dying  out  westward  in  the  river  valleys  of  the  prairie  States 
and  reappearing  in  the  mountains  of  southern  Mexico  and  Central 
America. 

The  number  of  known  fossil  species  of  hornbeam  considerably 
exceeds  the  number  of  species  now  living,  and  their  geographical 
range  was,  of  course,  greater.  The  hornbeam  is  not  certainly 
known  as  early  as  the  Upper  Cretaceous,  although  leaves  from 
the  late  Cretaceous  of  western  Greenland  were  described  by  Heer 
under  the  name  of  Carpinites  microphyllus,  and  these  may  well 
represent  the  earhest  known  hornbeam,  although  they  are  not 
especially  convincing.  That  the  hornbeams  originated  in  the 
North  seems  reasonable  because,  with  the  exception  of  two  sup- 
posed species  in  the  early  Eocene  of  France,  the  most  abundant 
Eocene  form  is  the  so-called  Carpimis  grandis  which  occurs  on 
the  Island  of  Sachalin  of  the  eastern  Asiatic  coast,  in  Alaska  over 
2000  miles  from  the  nearest  existing  occurrence,  in  British  Colum- 
bia, in  the  lignite  deposit  of  Brandon,  Vermont,  in  western  Green- 
land and  Spitzbergen — both  the  last  over  1000  miles  north  of  the 
existing  limits  of  the  genus.  Such  a  distribution  would  seemingly 
be  impossible  if  the  ancestral  forms  had  originated  in  low  latitudes. 

The  hornbeam  is  apparently  absent  from  the  extensive  Eocene 
floras  of  the  western  United  States  although  discovery  may  at 
any  time  disclose  it  in  that  region  where  it  might  be  expected  to 
have  been  present.  Nor  has  it  been  found  in  the  warmer  floras  of 
our  southeastern  States.  In  succeeding  Ohgocene  times  several 
hornbeams  have  been  found  in  Russia,  Germany,  Italy  and  France. 

The  Miocene  species  were  more  numerous  than  the  existing  forms, 
numbering  about  a  score.  They  occur  in  North  America  from 
Virginia  to  Colorado,  Nevada  and  Oregon;  and  in  the  Old  World 
from  Japan  and  Siberia  to  Spain.     No  less  than  17  diflferent  horn- 


110  TREE   ANCESTORS 

beams  grew  in  Miocene  Europe,  and  nearly  every  country  on  that 
continent  has  contributed  its  records,  although  there  appears  to 
have  been  a  massing  of  forms  in  southeastern  Europe  in  the  various 
states  and  crown  lands  that  formerly  constituted  the  Austrian 
empire. 

The  Phocene  records  include  7  or  8  forms  of  central  and  southern 
Europe.  That  North  America  has  furnished  no  Pliocene  horn- 
beams as  yet,  is  due  to  the  almost  complete  absence  of  suitable 
Pliocene  deposits.  That  hornbeams  were  present  at  that  time  is 
proved  by  their  presence  in  the  preceding  Miocene  and  succeed- 
ing Pleistocene  deposits.  Several  of  the  existing  hornbeams  appear 
during  Pleistocene  interglacial  periods,  in  regions  where  they  are 
still  found.  Thus  Carpinus  hetulus  and  Carpinus  orientalis  are 
recorded  from  the  Pleistocene  of  central  and  southern  Europe,  and 
our  American  hornbeam  has  been  found  fossil  in  the  Pleistocene 
of  Maryland,  North  Carolina,  Georgia  and  Alabama. 

THE    HOP   HORNBEAM 

The  hop  hornbeam  is  much  like  the  true  hornbeam  in  appear- 
ance and  habit,  but  frequents  better  drained  and  aerated  soils, 
and  is  less  northern  in  its  range.  The  most  obvious  difference 
between  the  two  trees  is  in  the  seed  bearing  catkins,  which  in  the 
hop  hornbeam  are  lax  and  terminal,  with  the  bracts  and  bractlets 
united  to  form  a  sac-Hke  envelope  to  each  flower,  and  these  by 
midsummer  have  enlarged  to  form  an  imbricated  green  cone-like 
affair  superficially  resembhng  a  hop  blossom — hence  the  common 
name  of  the  tree. 

The  scientific  name,  Ostrya,  was  the  classical  name  of  the  south 
European  tree.  The  existing  species  are  few  in  number  and  com- 
prise a  very  restricted  form  confined  to  the  canon  of  the  Colorado 
River  in  northern  Arizona ;  a  similarly  restricted  tree  in  Japan  and 
eastern  China;  the  common  hop  hornbeam  of  southern  Europe, 
Algiers  and  Asia  Minor;  and  the  common  American  tree,  often 
called  ironwood  because  of  its  hard  close  grained  wood.  The  last 
is  found  from  the  Gulf  of  St.  Lawrence  to  Dakota  and  southward 
to  northern  Florida  and  eastern  Texas,  reappearing  in  the  uplands 


HORNBEAM,   HAZEL,    BIRCH   AND   ALDER 


111 


of  southern  Mexico  (Orizaba,  Jalapa)  and  Guatemala,  where  they 
are  relics,  like  the  cypress  and  Carpinus,  of  the  former  greater  ex- 
tent of  these  forms  during  Pleistocene  times  or  earher,  which  have 
become  separated  from  their  fellows  by  the  arid  country  of  the 
Texas  border  and  northern  Mexico. 

Our  American  hop  hornbeam,  Ostrya  virginiana,  is  a  handsome 
tree,  of  small  or  medium  size,  with  an  open  crown,  rarely  over  70 


Fig.  22.    Sketch  Map  Showing  the  Existing  Range  and  Fossil 
Occurrences  of  the  Ironwood 


feet  tall  or  2  feet  in  trunk  diameter,  and  usually  much  less.  The 
yellowish  green  leaves  are  almost  indistinguishable  from  those  of 
the  hornbeam.  The  wood  is  heavy,  hard  and  tough,  with  a  close 
grain,  and  is  utilized  to  some  extent  for  fence  posts,  fuel,  and  small 
wooden  articles  such  as  tool  handles  and  mallets. 

The  geological  record  is  very  incomplete,  at  least  such  of  it  as 
has  been  deciphered  doubtless  partly  because  of  the  difficulty  of 


112  TREE    ANCESTORS 

distinguishing  Ostrya  leaves  from  those  of  Carpinus,  under  which 
name  perhaps  some  true  fossil  species  of  hop  hornbeam  may  be 
masquerading,  since  the  characteristic  winged  fruits  of  the  hop 
hornbeam  have  been  found  as  far  back  as  the  early  Tertiary.  The 
oldest  of  these  is  from  the  lower  Eocene  of  Texas.  Shghtly  younger 
are  similar  remains  described  by  Heer  from  western  Greenland. 
Two  species  have  been  recognized  in  the  Oligocene  of  France  and 
no  less  than  9  species  are  recorded  from  the  Miocene  and  Pliocene 
of  Europe  and  North  America.  These  occur  in  New  Jersey  and 
in  the  lake  basin  of  Florissant  in  Colorado  in  this  country;  and 
in  France,  Baden,  Germany,  Croatia,  and  Styria  in  Europe.  The 
known  Pleistocene  records  are  limited  to  the  occurrence  of  our 
existing  American  species  in  Japan,  Ontario  and  Alabama. 

THE    ALDER 

"But  here  will  sigh  thine  alder  tree." 

— Tennyson. 

Alders  are  not  remarkable  for  either  size  or  longevity,  neverthe- 
less they  were  associated  with  the  early  days  of  the  Anglo-Saxon 
race  and  have  taken  their  place  in  its  poetry  and  folk  lore.  The 
above  quotation  suggests  something  larger  than  the  small  shrubby 
"alders  by  the  brook"  that  Bryant  has  immortalized,  and  as  a 
matter  of  fact  several  of  the  alders  reach  a  height  of  40  to  50  feet, 
and  one — the  white  alder,  Alnus  rhombifolia,  of  the  Cascade  and 
Sierra  Nevadas — reaches  a  height  of  80  feet  and  has  a  tall  straight 
trunk  2  or  3  feet  in  diameter.  Most  of  the  alders,  however,  have  a 
distinctly  shrubby  appearance  even  when  50  feet  tall.  Alder  wood 
is  dense,  but  soft  and  brittle,  and  largely  sapwood,  hence  it  is  of 
slight  commercial  importance,  although  the  common  European, 
Algierian  and  Asiatic  Alnus  glutinosa  is  sometimes  a  timber  tree 
because  of  the  durability  of  its  wood  under  water,  but  even  it  is 
of  relatively  sHght  importance.  The  astringent  bark  and  cones 
are  also  used  to  some  slight  extent  in  tanning  and  medicine. 

The  scientific  name,  Alnus,  is  the  classical  name  of  the  alder. 
There  are  about  20  existing  forms,  half  of  which  occur  in  the  West- 
em  Hemisphere,  all  but  2  or  3  attaining  to  the  stature  of  trees. 


HORNBEAM,   HAZEL,    BIRCH   AND    ALDER 


113 


They  inhabit  swamps,  river  bottoms  and  moist  valleys  and  fog  belts 
of  high  mountains,  often  forming  conspicuous  thickets  on  mountain 
slopes. 

The  leaves  are  relatively  large,  in  general  somewhat  coarse  in 
appearance,  dark  green  in  color  and  shed  green  or  very  tardily 
taking  on  autumnal  tints.  They  are  straight  veined  and  with 
toothed  margins.     The  pollen  bearing  catkins  are  pendulous  form- 


FlG. 


23.  Sketch  Map  Showing  Existing  Range  and  Fossil  Occurrences 
Beyond  that  Area  of  the  Alder 


ing  the  preceding  season  and  discharging  in  early  spring  before  the 
leaves  unfold,  -quantities  of  golden  yellow  pollen  which  is  carried 
by  the  wind  to  the  female  flowers.  The  latter  develop  into  woody 
cones,  which  when  preserved  as  fossils,  simulate  sequoia  cones  and 
have,  more  than  once,  been  mistaken  for  them.  The  seeds,  really 
nutlets,  are  in  some  of  the  forms  winged  and  distributed  by  the 
wind,  in  others  they  are  wingless  and  distributed  by  streams. 


114  TREE    ANCESTORS 

That  these  methods  are  effective  is  shown  by  the  fact  that  the 
alder  has  penetrated  farther  into  South  America  than  ahnost  any- 
other  of  our  northern  trees,  and  we  can  merely  guess  at  the  vast 
lapse  of  time  represented  by  such  a  journey  from  Greenland  to 
BoUvia. 

The  alders  are  unobtrusive  modest  trees,  very  tolerant  of  shade 
from  their  youth,  consequently  gregarious  and  successful.  Some 
of  them  reach  farther  north  at  the  present  time  than  any  other 
members  of  the  family  except  the  small  Arctic  birches,  and  they  are 
the  only  representatives  of  this  large  family  that  cross  the  equatorial 
zone  and  maintain  themselves  in  the  Southern  Hemisphere. 

They  are  found  in  existing  floras  from  Alaska  to  Labrador  and 
southward  to  northern  Florida  and  the  uplands  of  Mexico  and 
Central  America  and  down  the  Andes  through  Colombia,  Ecuador 
and  Peru  to  BoHvia.  That  this  extension  into  South  America 
was  not  due  entirely  to  the  stimulus  of  northern  glaciation  is  shown 
by  the  presence  of  a  Pliocene  (i.e.,  a  preglacial)  species  in  Bolivia. 
In  the  Old  World  alders  are  found  from  Kamchatka  to  Spain,  and 
from  Norway  to  Algiers  and  Assam,  being  present  in  all  the  inter- 
vening great  mountain  systems. 

The  earhest  supposed  representatives  of  the  alder  consist  of 
"Upper  Cretaceous  forms  from  western  Greenland,  Silesia,  western 
Canada,  and  the  Dakota  sandstone  of  Minnesota  and  Nebraska — 

Fig.  24.  Some  Fossil  Birches  (About  f  Natural  Size) 

1.  Belnlites  Westii  latijolius  Lesq.,  from  the  Dakota  sandstone  of  Kansas. 

2.  2a.  Leaves  of  the  Arctic  birch,  Bdula  nana,  from  the  Interglacial  of 
Denmark. 

3.  Betula  grandifolia  Ettings.,  from  the  Upper  Eocene  of  Alaska. 

4.  Betula  coryloides  Ward,  from  the  early  Eocene  of  Montana. 

5.  Betula  oxydonta  Sap.,  from  the  Oligocene  of  France. 

6.  Betula  helcromorpha  Knowlton,  from  the  Eocene  of  Oregon. 

7.  7a,  7b.  Leaf  and  fruits  of  Betula  prisca  Ettings.,  from  Miocene  of  Austria. 

8.  Betula  Brongniarti  Ettings.,  from  the  Miocene  of  Austria. 

9.  9a.  Leaf  and  fruit  of  Betula  cuspidens  Sap.,  from  the  Upper  Oligocene  of 
France. 

10.  Fruit  of  Betula  dryadum  Brongn.,  from  the  Miocene  of  Europe. 


oD    ®!5 


7a  0^  ^       ^ 


Fig.  24 
115 


116  TREE   ANCESTORS 

all  of  somewhat  questionable  identity.  The  alders,  like  the  hazels, 
make  a  prominent  display  in  the  moist  temperate  floras  of  the 
Eocene,  no  less  than  a  score  of  species  haxang  been  described  from 
the  rocks  of  this  age,  in  which  they  are  represented  by  leaves,  cat- 
kins, cones,  and  wood.  True  alders  appear  in  the  earliest  Eocene 
of  France,  Wyoming,  Montana,  Dakota,  and  Colorado;  and  they 
are  especially  common  in  the  Eocene  rocks  of  Alaska,  Sachalin, 
Greenland,  Iceland  and  Spitzbergen.  Tertiary  species  of  alder 
have  been  described  from  both  Austraha  and  Tasmania,  but  these 
.are  not  certainly  iden tilled. 

Undoubtedly  the  earliest  flowering  plants  reached  Australia 
over  a  land  bridge  from  Asia,  but  until  the  plant  fossils  of  that 
region  receive  a  thorough  revision  at  the  hands  of  a  competent 
botanist,  too  great  rehance  cannot  be  placed  on  the  identifications 
of  the  early  students  of  these  floras.  If  authentic  these  Australian 
occurrences  mark  the  greatest  penetration  of  the  Southern  Hemi- 
sphere by  any  members  of  this  family,  and  almost  rival  the 
remarkable  southward  migration  of  the  beech  family. 

Ohgocene  alders  number  6  or  7,  and  are  confined  to  Europe, 
one  being  present  in  the  Baltic  amber  deposits.  As  I  will  have 
occasion  to  remark  in  connection  with  so  many  of  our  trees,  this 
paucity  of  Ohgocene  records  is  due  to  the  absence  or  lack  of  dis- 
covery of  Ohgocene  plant  beds  in  many  regions,  and  especially  in 
North  America.  However,  there  is  not  the  sHghtest  doubt  but 
that  there  were  Ohgocene  alders  at  that  time  in  both  North  America 
and  Asia. 

During  the  succeeding  Miocene  tune  the  geological  record  be- 
comes profuse  again  and  we  find  over  20  different  species  of  alders 

Fig.  25.  Some  Fossil  Leaves  and  Nuts  of  the  Hazel  (Slightly  Reduced) 

1.  Corylus  MacQuarrii  Heer,  from  the  Oligocene  of  France. 

2.  Corylus  americanu  fossilis  Newb.,  from  the  early  Eocene  of  Montana. 

3.  Corylus  Fosteri  Ward,  from  the  early  Eocene  of  JMontana. 

4.  Corylus  rostratajossilis  Newb.,  from  the  early  Eocene  of  Montana. 

5.  Hazel  nut  from  the  Oligocene  of  Saxony. 

6.  Hazel  nut  from  the  Oligocene  of  Baltic  Prussia. 


Fig.  25 
117 


118  TREE    ANCESTORS 

throughout  Eurasia  and  North  America.  They  are  especially 
prominent  in  the  lignite  beds  of  this  age  in  Europe,  which  represent 
fossil  swamp  deposits.  In  North  America  they  are  found  in 
California  and  Colorado,  eastern  North  America  being  especially 
deficient  in  Miocene  records  of  terrestrial  life. 

Except  for  Japan  the  numerous  Pliocene  forms  of  alders  are 
confined  to  European  locaHties  where  they  are  generally  distributed, 
being  especially  numerous  in  France  and  Italy.  At  this  time  again 
North  American  plant  records  are  very  scanty,  although  here  again 
there  is  no  reason  to  doubt  the  presence  of  alders  on  both  coasts, 
since  they  are  found  in  both  regions  in  the  succeeding  Pleistocene 
deposits. 

Of  the  7  or  8  alders  which  have  been  identified  from  the 
Pleistocene,  all  that  have  been  accurately  determined  represent 
still  existing  forms,  which  were,  indeed,  distinctly  foreshadowed 
during  the  Pliocene.  The  European  alder,  Alnus  glutinosa,  has 
been  found  in  the  Pleistocene  of  England,  Skye,  Germany  and 
Hungary.  Another  species  occurs  in  northern  Italy  at  this  time. 
The  hoary  alder,  Alnus  incana,  which  is  today  found  in  all  three 
of  the  northern  continents,  occurs  in  the  Pleistocene  of  Japan. 
In  North  America  the  red  alder,  Alnus  rubra,  occurs  in  Alaska;  the 
smooth  alder,  Alnus  incana,  has  been  found  in  Maryland,  and  a 
third  species  has  been  recorded  from  interglacial  deposits  in  Ontario. 


CHAPTER  XII 

The  Beech 

There  is  no  finer  sight  than  an  ancient  beech  woods,  or  even  a 
single  tree,  for  it  has  almost  the  ruggedness  of  the  oak,  and  a  more 
graceful  beauty  withal.  Its  smooth  light  colored  bark  fits  like  a 
glove,  and  from  time  immemorial  in  regions  where  there  were 
lads  and  lasses  the  boles  have  been  carved  with  initials,  impaled 
hearts,  and  lovers'  knots.  The  roots  have  a  habit  of  spreading 
near  the  surface  of  the  ground  so  that  they  show,  especially  on 
slopes  where  the  shaded  ground  is  subject  to  wash,  giving  them  the 
appearance  of  grimly  grasping  their  mother  earth  as  if  afraid 
of  separation. 

The  members  of  the  beech  family  (Fagaceae)  rival  those  of  the 
pine  family  from  a  utilitarian  point  of  view,  and  while  of  later 
origin  they  are  equally  enshrined  in  the  traditions  and  poesy  of 
the  Anglo-Saxon  race  and  in  the  practices  of  innumerable  crafts 
from  milHng  and  the  manufacture  of  wood-type  to  shipbuilding — 
once  a  craft  but  now  a  disease  in  its  iron  age  of  development. 

It  will  perhaps  be  possible  at  some  future  time  to  define  the 
demarcation  between  the  beeches,  oaks  and  chestnuts  that  comprise 
this  great  family  of  Fagaceae  and  to  trace  the  Hnes  of  descent  among 
the  hundreds  of  fossil  and  living  species  that  are  involved.  It  is 
easier  and  less  confusing  to  consider  the  single  line  to  which  the 
beech  belongs,  not  that  there  are  no  great  gaps  in  our  knowledge 
of  its  geologic  liistory,  especially  its  place  in  the  botanical  history 
of  the  great  area  of  Asia,  but  because  certain  striking  conclusions 
can  be  deduced  from  the  present  state  of  our  knowledge.  The 
beeches  (the  generic  name  Fagus  is  derived  from  the  classical 
0a7€ij/,  to  eat)  comprise  a  fairly  compact  group  of  species  formerly 
referred  to  the  single  genus  Fagus  (Linne,  1753)  well  illustrated 
by  the  common  beeches  of  Europe,  southeastern  North  America 
and  eastern  Asia. 

119 


120  TREE    ANCESTORS 

There  are  four  existing  species  of  Fagus  in  the  North  Temperate 
Zone.  Two  of  these  occur  in  the  coastal  region  of  eastern  Asia. 
The  American  beech,  formerly  much  utilized  in  the  manufacture 
of  charcoal,  is  now  largely  lumbered  for  a  wide  range  of  special 
commercial  uses  such  as  wooden  and  laundry  ware,  handles,  clothes 
pins,  shoes,  etc.,  since  the  wood  is  hard,  tough  and  strong  and  does 
not  decay  or  soften  under  water.  The  tree  ranges  from  Nova  Scotia 
westward  through  Ontario  to  Wisconsin  and  southward  to  western 
Florida  and  Texas.  It  frequents  rich  uplands  and  mountain 
slopes  in  the  northern  part  of  its  range  and  bottom  lands  in  the 
South,  reaching  its  maximum  development  in  the  lower  valley  of 
the  Ohio  and  on  the  slopes  of  the  southern  Alleghanies. 

Beech  was  abundant  nearly  everywhere  in  Colonial  America, 
but  the  wood  was  hard  to  spHt  and  decayed  quickly  upon  exposure 
to  weather,  so  that  the  pioneers,  with  a  fence  rail  point  of  view, 
had  a  very  small  opinion  of  it.  They  soon  discovered,  however, 
that  it  did  not  decay  or  soften  under  water,  so  that  quite  early 
they  utihzed  it  for  water  wheels,  and  especially  for  gudgeons  and 
bearings,  in  their  grist  and  saw  mills. 

The  charcoal  burners  early  learned  to  utilize  beech  and  we  find 
Peter  Kalm,  that  quaint  botanist  and  explorer  whose  name  is 
immortalized  in  the  genus  Kalmia  for  the  mountain  laurel,  writing 
in  1749  that,  next  to  black  pine  the  best  charcoal  for  smithing 
purposes  is  made  from  beech.  The  wood  is  difficult  to  work  in 
carpenter  shops,  but  it  finds  a  large  use  where  freedom  from  taste 
is  desirable  as  in  butchers,  blocks,  cutting  boards,  skewers,  ice 
cream  paddles,  tubs  and  pails  for  butter  and  lard,  and  hogsheads 
for  sugar  and  molasses.  Picnic  plates  are  now  made  by  the  mil- 
lions of  beech  wood,  which  also  takes  an  important  place  in  the 
manufacture  of  kitchen  and  laundry  appliances,  blocks,  agricultural 
impliments,  furniture,  flooring  and  fixtures. 

The  fourth  existing  species  is  the  European  beech  and  its  horti- 
cultural varieties.  It  is  one  of  the  common  forest  trees  of  temper- 
ate Europe  from  southern  Norway  and  Sweden  to  the  Mediterran- 
ean, ascending  to  elevations  of  five  thousand  feet  in  the  Swiss 
Alps.  It  is  common  in  southern  Russia  and  throughout  Asia 
Minor  to  northern  Persia. 


THE   BEECH  121 

The  common  name  of  beech  is  from  the  Anglo-Saxon  hoc,  bece 
or  beoce,  the  German  buche,  the  Swedish  box— all  words  signifying 
book  as  well  as  beech  and  derived  from  the  Sanscrit  boko  or  letter 
and  bokos  or  writings.  This  connection  of  the  vernacular  name  of 
the  tree  with  the  graphic  arts  is  supposed  to  have  originated  from 
the  fact  that  the  old  Runic  tablets  were  of  beechwood.  At  any 
rate  in  beech  we  probably  have  the  oldest  existing  name  of  any 
wood  in  the  world. 

The  beech  has  been  utilized  by  the  natives  of  Europe  since  pre- 
historic times,  a  fact  shown  by  the  presence  of  its  remains  in  the 
deposits  of  the  Swiss  Lake  dwellings  of  the  Neolithic  period,  or 
younger  stone  age  (about  7000  B.C.).  It  is  one  of  the  largest  of 
British  trees,  especially  on  chalky  or  sandy  soils.  Beech  mast, 
formerly  known  as  "buck,"  was  not  only  a  subject  of  medieval 
local  legislation,  but  it  even  gives  its  name  to  the  county  of  Buck- 
ingham. 

It  is  obvious  from  the  interrupted  distribution  of  these  4 
existing  species,  namely,  1  in  Europe,  1  in  southeastern  North 
America  and  2  in  eastern  Asia,  strikingly  shown  on  the  accom- 
panying sketch  map,  that  these  existing  species  are  the  isolated 
remnants  of  a  distribution  which  in  late  geologic  time  must  have 
covered  the  intervening  areas  and  embraced  practically  the  whole 
Northern  Hemisphere.  This  supposition  derived  from  a  study  of 
the  present  ranges  of  the  4  existing  species  will  subsequently 
be  shown  to  be  somewhat  less  rather  than  the  whole  story  which 
geologic  history  elucidates. 

With  the  exploration  of  antipodean  lands  during  the  last  century 
about  a  dozen  forms  of  beech-like  trees  and  shrubs  were  discovered 
in  New  Zealand,  Austraha,  Tasmania,  Chile  and  Terra  del  Fuego. 
Some  of  these  were  found  to  only  attain  the  stature  of  shrubs, 
many  of  them  were  evergreen  and  all  had  tiny  leaves.  They 
differ  from  the  northern  beeches  in  their  partial  lack  of  deciduous 
habits,  their  smaller  leaves  and  in  their  flowers  being  solitary  or 
grouped  in  clusters  of  three.  For  a  long  time  these  southern  forms 
were  referred  to  the  genus  Fagus,  which  was  divided  into  two 
sections — a  section  Eufagus  for  the  well  known  species  of  the  north 


122  TREE   ANCESTORS 

temperate  zone  and  a  section  Nothofagus  for  their  antipodean 
congeners.  The  latter  have  since  been  raised  to  generic  rank, 
quite  rightly  it  seems  to  me,  although  their  close  relationships  and 
community  of  origin  with  the  true  beeches  is  clearly  demonstrable. 
The  curiously  segregated  ranges  of  these  existing  forms  is  shown 
on  the  accompanying  sketch  map. 

Granting  that  these  two  lines  are  offshoots  of  a  common  stock 
the  question  of  its  original  home  at  once  suggests  itself,  along 
with  the  query  as  to  whether  in  some  past  time  members  of  the 
2  genera  flourished  side  by  side  either  in  the  north  or  the  south  tem- 
perate zone.  These  questions  can  only  be  answered  by  an  appeal 
to  the  fossil  record,  a  book  wdth  unfortunately  many  missing 
chapters,  especially  those  relating  to  the  great  land  mass  of  Asia. 

The  oldest  known  fossil  forms  are  a  species  {Fagus  prisca  Ettings- 
hausen)  from  the  early  Upper  Cretaceous  (Cenomanian)  of  Saxony 
and  three  species  in  the  Dakota  sandstone  of  the  western  United 
States  of  almost  exactly  the  same  age  as  the  Saxon  species.  Their 
essentially  contemporaneous  appearance  in  Europe  and  America 
argues  that  they  were  immigrants  into  both  regions  from  some  third 
area.  Only  two  alternatives  are  probable.  Either  their  ances- 
tors came  from  the  Arctic  region  and  spread  southward  simulta- 
neously into  Europe  and  America  or  else  they  originated  in  Asia 
and  spread  westward  into  Europe  and  eastward  into  America 
across  the  land  bridge  which  closed  Behring  Sea  at  about  this 
time.  If  the  Arctic  was  the  original  home  of  the  beech  its  remains 
should  occur  in  either  the  Cenomanian  or  later  Cretaceous  floras 
of  Greenland  where  it  has  not  been  found  although  it  is  present 
in  that  region  in  the  Tertiary.  Furthermore  if  it  had  originated 
in  the  north  it  should  have  been  a  member  of  that  migratory  wave 
of  vegetation  that  swept  southward  along  the  east  coast  of  North 
America  at  about  the  dawn  of  the  Upper  Cretaceous.  Our  east 
coast  Cretaceous  contains  a  very  large  flora  found  in  deposits  of 
this  age  from  Marthas  Vineyard  to  Alabama  and  this  flora  had  a 
great  many  elements  in  common  with  the  Greenland  Cretaceous 
flora.  No  traces  of  Cretaceous  beeches  have,  however,  been  dis- 
covered along  the  Atlantic  coast. 


THE   BEECH  123 

If,  on  the  other  hand,  Fagus  originated  in  the  Asiatic  region  it 
would  have  had  an  almost  latitudinal  pathway  with  broad  and 
uniform  land  surfaces  both  westward  to  Europe  and  eastward  to 
western  North  America,  the  latter  region  almost  entirely  cut  off 
from  eastern  North  America  by  an  epicontinental  sea.  The  pres- 
ence of  petrified  beech  wood  in  the  Cretaceous  of  Japan,  of  Germany 
and  in  the  Eocene  of  the  Caucasus,  as  well  as  leaves  in  the  Creta- 
ceous of  Vancouver  Island  and  in  the  Eocene  of  Alaska  and 
the  early  Tertiary  of  AustraKa  would  similarly  accord  with  this 
hypothesis  of  its  center  of  radiation  better  than  any  other. 

The  Eocene  records  also  embrace  various  North  American  and 
European  forms  which  offer  no  difficulties  on  such  a  theory,  nor 
do  the  numerous  succeeding  Ohgocene  and  Miocene  species  of  the 
northern  hemisphere.  The  antipodean  records,  of  which  there 
are  a  considerable  number,  seem  at  first  thought  to  offer  greater 
difficulties.  In  deposits  the  age  of  which  is  unfortunately  some- 
what uncertain  but  which  are  either  Eocene  or  Oligocene,  4 
species  of  Fagus  are  found  in  southern  South  America — three  in 
Chile  and  3  in  Terra  del  Fuego  and  a  fifth  is  found  on  the  edge 
of  the  Antarctic  continent  in  Graham  Land.  They  are,  in  all  of 
these  locaUties,  associated  with  an  abundant  display  of  Nothofagus, 
no  less  than  10  species  from  Chile,  Patagonia,  Terra  del  Fuego  and 
Graham  Land  having  been  described  by  Engelhardt  and  Dusen. 
The  Tertiary  species  of  Fagus  in  the  Austrahan  region  are  likewise 
associated  with  four  or  five  species  of  Nothofagus.  Another  species 
is  found  in  Tasmania  and  there  are  several  in  the  outlying  region 
of  New  Zealand,  one  of  the  latter  being  common  to  eastern  Australia. 

It  would  be  an  attractive  hypothesis  to  consider  Fagus  as  of 
northern  origin  and  Nothofagus  as  having  originated  independently 
on  the  broad  bosom  of  the  Antarctic  continent,  from  whence  it 
spread  northward  into  southern  South  America  on  the  one  hand^ 
Tasmania  and  eastern  Australia  on  the  other,  and  to  New  Zealand 
by  a  third  route  from  the  south  northward.  Such  a  theory  would 
be  in  accord  with  many  recent  discussions  of  geographical  distri- 
bution. It  would  almost  certainly  be  suggested  by  plant  geog- 
raphers who  lacked  any  knowledge  of  antecedent  floras  by  the 


124  TREE    ANCESTORS 

peculiar  distribution  of  the  existing  species  of  Nothofagus,  namely, 
a  dozen  very  similar  species  about  equally  distributed  between 
southern  South  America  (Chile  and  Terra  del  Fuego),  South 
Australia  and  Tasmania,  and  New  Zealand. 

This  attractive  hy])othesis  is,  I  beheve,  entirely  erroneous,  and 
for  the  following  reasons:  It  would  entirely  fail  to  account  for 
the  distribution  of  Fagus,  which  is  clearly  of  northern  origin  and 
yet  is  associated  with  Nothofagus  in  the  Tertiary  of  South  America, 
Graham  Land  and  Australia.  Moreover  what  appears  to  be  true 
species  of  Nothofagus  occur  in  the  Oligocene  of  Greece  {Fagus 
pygmaca  Unger  and  Fagus  chamaephegos  Unger).  If  on  the  other 
hand  Nothofagus  was  of  Holarctic  origin  it  would  reach  these  an- 
tipodean lands  along  with  Fagus.  A  number  of  elements  of  the 
Dakota  sandstone  flora  (Upper  Cretaceous)  are  found  in  the  later 
Cretaceous  of  Argentina,  showing  that  migration  from  North 
America  into  southern  South  America  was  not  only  possible  but 
actually  took  place  during  the  Upper  Cretaceous  and  all  lines  of 
evidence — bathymetric,  tectonic,  petrographic  and  paleontologic, 
indicate  that  South  America  was  in  direct  connection  with  Antarc- 
tica. The  Australian  species  would  have  reached  Austraha,  Fagus 
and  Nothofagus  together  or  in  successive  migrations  either  from 
southeastern  Asia  or  from  Antarctica  over  the  then  existing  land 
connections. 

New  Zealand  offers  more  difficulties  but  there  is  really  a  vast 
amount  of  paleobotanical  and  botanical  evidence  (the  latter  dis- 
cussed by  Alfred  Russell  Wallace  in  his  "Island  Life")  indicating 
a  common  origin  for  the  Australian  and  New  Zealand  floras. 
There  may  have  been  a  direct  interchange  of  floral  elements  by 

Fig.  26.  Some  Fossil  Leaves  and  Fruits  op  the  Beech  (Natural  Size) 

1.  Fagus  cretacea  Newberry  from  the  Upper  Cretaceous  of  Kansas. 

2.  Fagus  feroniae  Unger  from  the  Miocene  of  Bohemia. 

3.  Fagus  horrida  Ludwig.     Bur  from  the  Miocene  of  Germany. 

4.  Fagus  lamhericnsis  Berry  from  the  Pliocene  of  Alabama. 

5.  Fagus  intermedia  Ettingshausen.     Nut  from  the  Eocene  of  England. 
6-8.  Fagus  Jerruginca  Alton.     Bur,  nut  and  leaf  from  the  Pleistocene  of 

North  Carolina. 


Fig.  26 
125 


126  TREE   ANCESTORS 

way  of  the  since  sunken  lands  indicated  by  the  topography  of  the 
ocean  bottom  and  by  the  coral  islands  and  tectonic  (structural) 
lines  across  Polynesia. 

It  seems  probable,  however,  that  Australia  and  New  Zealand 
were  never  actually  connected  in  later  geological  times,  that  is  to 
say,  since  the  higher  plants  were  evolved.  Otherwise  New  Zealand 
should  contain  some  traces  of  the  animals,  such  as  the  marsupials, 
and  plants  such  as  the  Eucalyptus  or  gums  that  particularly  char- 
acterize the  life  of  Australia.  New  Zealand  has,  however,  been 
shown  to  have  been  much  more  extensive  in  former  than  at  the 
present  time,  and  it  seems  probable  that  it  received  its  beeches 
from  the  Antarctic  continent  during  one  of  these  times  of  extension 
rather  than  by  a  land  bridge  between  New  Zealand  and  Australia. 

If  Fagus  or  even  Nothofagus  were  of  southern  origin,  and  I 
think  that  it  will  be  conceded  by  botanists  familiar  with  the  two 
genera  that  they  are  the  immediate  descendants  of  a  common 
stock,  it  would  be  contrary  to  the  general  rule  of  past  distribution 
of  the  ancestors  of  our  existing  flora  which  in  every  case  that  has 
been  investigated  show  former  cosmopolitanism  in  the  great  land 
mass  of  the  northern  hemisphere  and  a  simultaneous  or  subsequent 
migration  into  southern  lands.  This  statement  is  notably  true 
of  the  coniferous  genera  Araucaria  and  Dammara.  It  is  likewise 
true  of  the  great  antipodean  families  Proteaceae  and  Myrtaceae, 
and  many  other  and  no  less  striking  instances  could  be  enumerated. 

It  would  seem  that  Nothofagus  was  more  primitive  than  Fagus, 
or  at  least  that  it  is  more  like  the  original  stock  from  which  both 
took  their  origin.  This  stock  was  probably  evergreen  in  habit, 
small  in  size  and  with  relatively  reduced  leaves.  If  this  supposi- 
tion is  justified  it  might  be  considered  as  furnishing  another  argu- 
ment for  the  northern  origin  and  southward  migration  of  the 
original  stock,  for  the  natural  place  to  look  for  existing  forms  most 
Hke  their  remote  ancestors  has  been  considered  by  some  students 
of  distribution  as  being  farthest  away  from  the  original  center 
of  radiation — nearer  this  center  they  would  tend  to  have  been 
replaced  by  successively  later  and  later  evolved  forms. 


THE   BEECH  127 

The  actual  details  of  the  past  history  of  the  beeches  were  of 
course  infinitely  more  compKcated  than  I  have  sketched  them. 
All  of  the  new  species  did  not  originate  successively  in  one  area 
and  radiate  from  it  regularly  in  all  directions.  Each  continental 
area  must  have  been  a  local  center  of  evolution  and  radiation  after 
the  stock  had  once  reached  it,  and  doubtless  there  were  interchanges 
between  one  and  another  parts  in  progress  during  the  whole  of  the 
long  ages  of  the  Tertiary  period.  Nevertheless  the  foregoing 
sketch  shorn  of  its  unknown  and  confusing  complexities  emphasizes 
the  major  features  of  beech  evolution  and  migration. 

It  remains  for  me  to  consider  the  recorded  occurrences  of  beeches 
during  past  time  somewhat  more  fully  than  I  have  done  in  the 
preceding  paragraphs.  The  Cretaceous  species  have  already  been 
enumerated  in  the  paragraphs  discussing  the  probability  of  Asia 
having  been  the  original  home  of  Fagus  and  Nothofagus.  The 
Eocene  species  are  nine  or  ten  in  number  and  include  records  from 
Europe,  Greenland,  Alaska  and  the  western  United  States.  The 
Oligocene  species  number  about  14  and  the  records  include 
eastern  and  southwestern  Asia,  j)robably  Australia,  all  the  coun- 
tries of  Europe  where  plants  of  this  age  are  represented,  eastern 
North  America,  Graham  Land,  Chile  and  Terra  del  Fuego.  The 
Miocene  species  number  about  30.  Fagus  at  this  time  was 
practically  cosmopolitan,  being  represented  throughout  Europe 
and  North  America,  particularly  in  the  west  in  the  Rocky  moun- 
tain province  (Colorado)  and  along  the  Pacific  coast  (California) 
where  it  has  now  long  been  extinct.  It  was  present  in  Iceland  and 
Spitzbergen,  in  Austraha,  and  at  several  points  in  eastern  Asia. 
The  Pliocene  species  number  over  a  score  and  include  several 
that  foreshadow  forms  that  are  present  in  our  recent  floras.  The 
records  include  Japan  and  most  Pliocene  plant  localities  in  Europe. 
In  the  United  States  where  Pliocene  deposits  other  than  those  of 
strictly  marine  origin  (and  consequently  lacking  fossil  plants)  are 
very  rare,  an  extinct  species  of  Fagus  is  found  in  Alabama  along 
the  Gulf  coast  of  that  period.         / 

Beech  forests  seem  to  have  flourished  in  midiminished  vigor 
over  most  of  the  northern  hemisphere  up  to  the  advent  of  the 


128  TREE   ANCESTORS 

glacial  period,  although  their  continuous  range  had  already  been 
interrupted  by  the  formation  of  mountain  ranges  like  those  of  the 
western  United  States  or  those  of  central  Asia  which  by  their  in- 
terference with  the  chmatic  equihbrium  caused  the  development  of 
vast  stretches  of  arid  or  semi-arid  country  Hke  that  of  the  present 
day  in  central  and  southwestern  Asia  and  in  our  own  western  and 
southwestern  states. 

The  Pleistocene  records  of  the  beech  include  the  remains  of 
wood,  of  an  abundance  of  leaves  as  well  as  of  nuts  and  husks,  the 
latter  almost  always  present  in  buried  swamp  deposits.  These 
records  embrace  an  extinct  species  in  Japan,  remains  of  the  still 
existing  Fagtis  japonica,  and  other  leaves  in  that  country  which 
are  distinguished  with  difficulty  from  the  European  beech.  The 
latter,  Fagiis  sylvatica,  occurs  in  England,  Germany  and  southern 
Europe  at  this  time  and  is  often  associated  with  traces  of  Neolithic 
man.  The  American  beech,  variously  denominated  {e.g.,  Fagus 
ferruginea  Alton,  Fagus  americana  Sweet,  Fagus  atropimicea 
(Marsh)  Sudworth,  and  Fagus  grandifolia  Ehrhart),  is  wide- 
spread in  Pleistocene  deposits.  It  is  found  in  the  Port  Keimedy 
bone  cave  in  Pennsylvania ;  in  the  bluffs  of  the  Mississippi  in  west- 
em  Kentucky;  in  the  high  river  terraces  of  West  Virginia,  and  in 
buried  swamp  deposits  in  Maryland,  Virginia,  North  Carolina 
and  Alabama. 

In  the  foregoing  brief  sketch  I  have  refrained  from  saying  much 
about  the  utility  of  the  beeches  or  of  the  surpassing  beauty  of  their 
Hght  smooth  bark  and  glossy  symmetrical  foliage.  Beech  woods 
are  the  common  heritage  of  the  Anglo-Saxon  race  and  are  inti- 
mately associated  with  our  ancestors  during  the  time  that  they 
were  slowly  emerging  from  barbarism.  Ages  later  they  furnished 
the  best  fuel  for  the  open  hearth  heating  and  cooking  of  our  more 
immediate  ancestors  and  along  with  the  oaks  furnished  the  mast 
for  the  swine  that  roamed  the  forests  of  the  feudal  barons. 

The  mist  of  tradition  and  history  that  clothes  the  beech  should 
inevitably  awaken  some  of  the  thrill  corresponding  to  that  awak- 
ened by  a  visit  to  some  scene  of  ancient  romance  or  tradition  such 
as  Kenilworth  Castle,  Palestine  or  the  scenes  of  classic  Greece  or 
imperial  Rome. 


CHAPTER  XIII 

The  Oak  and  Chestnut 

The  family  to  which  the  oak  and  the  chestnut  belong  is  now  called 
the  Fagaceae  and  includes  the  beech  as  well  as  various  other  tree 
types  not  familiar  to  the  residents  of  the  United  States.  The  beech 
has  been  discussed  in  a  separate  chapter,  and  the  present  chapter 
will  be  devoted  to  the  oak  and  chestnut  after  some  mention  is 
made  of  these  other  genera.  The  first  of  these  is  one  called  Casta- 
nopsis  wliich  has  about  30  existing  forms  with  evergreen  leaves  and 
found  from  the  Himalayas  and  tropical  India  to  Hong  Kong,  and 
represented  on  our  Pacific  coast.  Castanopsis  is  intermediate 
between  the  true  oaks  and  the  chestnut,  and  its  presence  on  both 
shores  of  the  Pacific  indicates  that  its  ancestors  must  have  flourished 
in  the  intermediate  country  and  over  the  land  bridge  connecting 
North  America  and  Asia  in  the  Behring  Sea  region  at  some  past 
time  when  the  climate  of  these  northern  lands  was  more  genial  than 
it  is  today.  Pasania  is  a  second  genus  of  existing  oak-like  plants 
with  over  100  species  in  the  southeastern  Asiatic  region,  and  hke 
Castanopsis,  it  is  represented  on  our  Pacific  coast  by  a  single  form 
which  ranges  from  southwestern  Oregon  to  southern  Cahfornia, 
separated  from  its  100  Oriental  congeners  by  the  whole  breadth 
of  the  Pacific  ocean.  This  western  form  is  the  so-called  Tanbark 
oak,  the  Quercus  densifolia  of  Hooker  and  Arnott. 

There  seems  to  be  no  doubt  but  that  all  of  these  and  the  other 
members  of  the  oak  family  are  the  diversified  descendants  of  a  com- 
mon Cretaceous  stock.  This  ancestral  stock  is  represented  by  the 
extinct  genus  Dryophyllum  which  is  first  recognized  in  the  Upper 
Cretaceous  at  which  time  it  was  not  only  abundant  and  varied 
but  widespread.  Its  leaves  were  of  the  chestnut,  entire  or  holly 
oak  type,  and  possessed  a  characteristic  arrangement  of  the  veins 
which  usually  enables  them  to  be  readily  recognized  and  distin- 
guished from  those  of  the  oak,  chestnut  or  beech.     They  were 

129 


130 


TREE    ANCESTORS 


especially  abundant  among  the  sand  dunes  that  at  that  time  bor- 
dered the  Upper  Cretaceous  sea  in  northern  Europe  (Aix-la-Cha- 
pelle,  Bohemia  and  Silesia).  They  were  also  abundant  around  the 
shores  of  the  late  Upper  Cretaceous  sea  in  the  Mississippi  valley 
where  one  of  them  has  been  given  the  significant  Latin  name  of 
protofagus,  and  may  actually  represent  the  starting  point  of  the 
beech  line  of  descent.  Dryophyllum  also  occurs  in  beds  of  Upper 
Cretaceous  age  in  western  Greenland,  and  there  are  several  species 
recorded  from  deposits  of  this  age  in  Montana,  Wyoming  and 
Colorado.  They  have  even  been  recorded  from  Australia,  but 
these  last  records  are  not  regarded  as  authentic.  Dryophyllum 
is  even  more  abundant  in  the  early  Eocene  than  it  was  in  the  late 
Cretaceous.  Here  in  America  there  are  5  abundant  and  very 
characteristic  forms  in  the  early  Eocene  of  the  Gulf  states.  There 
are  3  recorded  from  Colorado,  1  from  Wyoming,  1  from  the  Yellow- 
stone Park,  CaHfornia  and  British  Columbia.  Another  is  common 
in  the  late  Eocene  of  Alaska  and  Sachalin  Island  at  the  opposite 
ends  of  the  land  bridge  of  which  the  central  planking  has  since  worn 
away  to  form  Behring  straits.  In  the  early  Eocene  of  Europe, 
which  many  geologists  call  the  Paleocene,  there  are  abundant 
leaves  of  4  species  of  Dryophyllum  in  Belgium,  3  in  France  and 
another  in  Italy.  By  Oligocene  times  only  3  doubtful  forms  are 
known  in  France  and  Italy.  It  is  true  that  6  have  been  recorded 
from  the  late  Tertiary  of  Indo-China,  but  the  name  Dryophyllum 
is  used  for  these  in  the  sense  that  it  represents  doubtful  members 
of  the  Fagaceae,  and  not  in  a  strict  botanical  sense. 

Dryophyllum 


Quercus 
oaks 


Pasania 


I 
Castanopsis 


I 
Nothofagus 


Castanea 
chestnuts 


Fagus 
beeches 


DiAGR.\M  Showing  the  Interrelationships  of  the  Oaks,  Chestnuts 
AND  Beeches 


THE    OAK    AND    CHESTNUT  131 

The  relation  of  the  various  modern  genera  to  one  another  and 
to  the  ancestral  Dryophyllum  stock  is  shown  in  the  accompany- 
ing diagram.  Space  does  not  permit  of  a  detailed  discussion  of 
most  of  these  genera  even  were  such  a  treatment  desirable,  which 
it  is  not,  since  Pasania  and  Castanopsis  are  unfamiliar  to  most  of 
my  readers  and  are  sort  of  alien  immigrants  from  Asia  that  have 
survived  on  our  Pacific  coast. 

THE    OAK 

"Jove's  own  tree, 
That  holds  the  woods  in  awful  sovereignty." 

— ^Virgil,  Georgics. 

The  oak  has  always  been  an  object  of  veneration  or  of  senti- 
mental tradition  by  all  of  the  seafaring  nations  of  history  with  the 
possible  exception  of  the  Phoenicians  and  the  Norsemen.  By  the 
Greeks  it  was  believed  to  have  been  the  first  tree,  and  it  was  sacred 
to  Zeus.  An  oak  had  sheltered  his  cradle  on  Mount  Lycaeus  and 
he  was  believed  to  haunt  the  sacred  oak  at  Dodona.  The  oak 
has  also  frequently  been  the  object  of  worship  of  the  various  tree 
worshipping  cults  of  the  Old  World — the  very  name  Druid  is  said 
to  have  come  from  the  root  deru,  the  Celtic  for  oak. 

We  read  in  the  Old  Testament  that  Jehovah  appeared  to  Abra- 
ham beneath  the  oak  tree  at  Mamre  in  Hebron,  and  in  later  days 
the  natives  built  altars  to  the  supposed  Abraham's  oak  (terebinth) 
which  were  eventually  destroyed  by  order  of  the  religious  Constan- 
tine,  who  caused  a  church  to  be  erected  to  replace  them.  That 
the  earlier  Hebrews  were  frequently  tree  worshippers  is  further 
indicated  in  the  story  of  Gideon:  And  it  was  under  an  oak  which 
was  in  Ophrah  that  the  angel  of  the  Lord  came  to  Gideon  and  told 
him  that  it  was  he  who  was  to  save  Israel  from  the  Midianites. 

In  later  days  there  was  a  great  oak  at  Geismar  in  Hesse  dedicated 
to  Jupiter  and  this  was  felled  by  order  of  Bonifacius,  and  a  chapel 
to  Saint  Peter  was  constructed  of  its  timber.  At  Kildare  in 
Ireland,  the  name  being  derived  from  the  Gaelic  cilldara  or  church 
of  the  oak,  tradition  has  it  that  Saint  Bridget  built  her  church  under 
an  oak  tree.     The  oak  and  the  mistletoe  associated  with  it  in 


132 


TREE    ANCESTORS 


Britain  were  a  part  of  the  druidical  cult,  and  in  the  more  modern 
days  it  was  beheved  that  the  spirit  of  the  oak  took  refuge  in  the 
mistletoe  during  the  winter  when  the  tree  was  leafless.  The  asso- 
ciation of  the  mistletoe  with  Christmas  grew  out  of  the  former 
belief  and  the  custom  of  bringing  the  mistletoe  into  the  house  in 
order  that  the  tree  spirit  might  bring  fertility  to  the  homesteaders. 


Fig.  27.  Sketch  Map  Showing  the  Existing  Distribution  of  Oaks 


There  are  historic  oaks  in  ahnost  every  region  where  oak  trees 
of  outstanding  size  and  longevity  are  to  be  found.  Among  these 
may  be  mentioned  Charlemagne's  oak  in  the  forest  of  Fontain- 
bleau;  the  Abbott's  oak  at  Woburn  Abbey  where  Henry  VIII 
hung  the  Abbott  in  1537;  the  oak  in  the  New  Forest  against  which 
the  arrow  is  said  to  have  glanced  that  killed  William  Rufus;  the 
royal  oak  at  Boscobel  in  which  Charles  II  hid  after  the  disastrous 


THE    OAK   AND   CHESTNUT  133 

battle  of  Worcester;  the  William  Wallace  oak  at  Torwood;  Alfred's 
oak  at  Oxford;  the  Charter  oak,  that  bulwark  of  liberty  at  Hart- 
ford, Connecticut,  and  the  Wye  oak  on  the  eastern  shore  of 
Maryland. 

The  oak  is  especially  esteemed  by  the  Anglo-Saxon  race  not  only 
as  the  monarch  of  the  forest  which  turned  into  ships  should  forever 
preserve  English  liberty,  but  more  particularly  as  a  fit  symbol  of 
the  sturdy  Anglo-Saxon  character,  that  might  yield  to  adversity 
but  which  was  not  to  be  uprooted  or  changed  by  passing  storms. 
A  like  recognition  of  the  sturdy  oak  in  still  earlier  days  would  seem 
to  have  been  the  inspiration  for  the  use  of  oak  leaves  as  a  civic 
crown  by  the  Romans,  who  also  dedicated  the  tree  to  ^Esculapius, 
probably  because  of  its  healthy  longevity. 

Not  only  did  maritime  folk  early  come  to  appreciate  oak  plank- 
ing, but  the  more  lowly  keepers  of  the  swine  Hkewise  had  their 
reasons  for  appreciating  the  bounty  of  the  oak,  in  fact  the  Greek 
choiros,  a  pig,  is  in  allusion  to  oak  mast,  and  acorns  were  beheved 
to  have  been  the  staple  food  of  humanity  in  those  far  distant 
days  before  Demeter  had  introduced  grain  upon  the  earth.  We 
find  that  the  British  forests  are  enumerated  in  the  Doomsday  Book 
by  the  number  of  hogs  they  could  fatten.  Our  Latin  name  for 
the  oak  tribe,  Quercus,  is  said  to  have  been  derived  from  the 
Celtic  quer  or  fine  and  cuez  or  tree,  so  that  it  will  come  as  something 
of  a  shock  to  learn  of  the  tiny  oaks  only  a  few  inches  high  and 
with  spreading  underground  stems  like  the  Quercus  minima  of 
Florida,  or  to  learn  of  the  vast  oak  forests  in  Mexico  and  Central 
America  with  their  strange  undergrowth  of  small  palms,  tree 
ferns  and  tropical  climbers. 

Although  the  oak  may  be  the  monarch  of  the  forest  in  the  tem- 
perate cKmes  of  the  Northern  Hemisphere  it  is  by  no  means  con- 
fined to  those  regions  but  is  well  represented  in  most  tropical 
countries  except  the  uplands  of  Africa  and  South  America  where 
oaks  have  apparently  never  reached  farther  south  than  the  moun- 
tains of  Colombia.  There  are  a  number  of  oaks  in  the  West  Indies, 
and  over  300  different  kinds  are  recorded  from  Central  America. 
Both  shores  of  the  Mediterranean  as  well  as  the  Caribbean  have 


134  TREE    ANCESTORS 

their  oaks  and  there  are  several  species  in  tropical  Asia  and  the 
East  Indies  as  far  as  New  Guinea. 

Although  so  abundant  at  the  present  time  the  oaks  represent  a 
very  old  type  of  tree,  this  would  be  inferred  from  their  present 
distribution  even  though  nothing  were  known  of  their  geological 
history.  Considerable  of  this  ancestral  history  is  known,  however, 
but  not  in  enough  detail  to  do  more  than  sketch  its  more  general 
outlines.  Nor  is  the  information  about  the  existing  oaks  complete 
enough  to  aid  greatly  in  an  attempt  to  outhne  the  past  migrations 
and  evolution  of  the  various  forms.  DeCandolle's  monograph  of 
the  existing  oaks  published  in  1864  enumerated  281  species.  Since 
that  date  much  has  been  learned  about  oaks  in  general  and  much 
more  about  the  maze  of  species  inhabiting  the  uplands  of  Mexico 
and  Central  America.  In  a  recent  publication  Trelease  recognizes 
354  species  in  America  alone  so  that  there  must  be  about  500 
existing  species  in  the  present  floras  of  the  world. 

Both  Saporta  and  Ettingshausen  have  sought  to  untangle  the 
web  of  distribution  and  the  geological  history  of  the  oaks,  but  it 
must  be  confessed  with  rather  indifferent  success.  Explanation 
must  still  wait  upon  lagging  information,  and  the  present  attempt 
must  be  considered  one  of  generalities  rather  than  of  details.  A 
great  many  fossil  leaves  have  been  described  as  oaks,  but  a  large 
number  of  these  have  no  claim  to  such  a  relationship.  The  problem 
of  identification  of  oak-like  leaves,  particularly  in  the  mixed  floras 
of  the  Upper  Cretaceous  and  Eocene  periods  is  most  difficult  of 
solution.  When  the  botanist  compares  these  fossil  leaves  with 
only  those  of  the  familiar  temperate  trees  he  is  frequently  misled. 
For  example,  supposed  oaks  in  the  lower  Eocene  floras  of  our 
southern  states  have  been  found  to  represent  an  entirely  different 
family  of  plants,  the  Dilleniaceae,  at  present  not  found  in  the  United 
States.  Similarly  several  oaks  were  described  from  PHocene 
deposits  in  the  state  of  Bahia,  Brazil,  which  if  authentic  would 
represent  a  remarkable  extension  of  their  known  range.  I  have  not 
seen  the  actual  specimens  upon  which  Baron  Ettingshausen  based 
these  determinations,  but  I  have  examined  large  collections  from  the 
same  outcrop  from  which  his  specimens  came,  and  these  represent 


THE    OAK   AND    CHESTNUT 


135 


an  entirely  different  floral  assemblage  without  any  traces  of  oaks, 
which,  furthermore  would  be  entirely  out  of  place  in  such  an 
assemblage. 

In  our  latitudes  the  oaks  are  almost  entirely  trees  which,  as  a 
rule,  grow  slowly  and  are  long  hved  and  agressive  trees.  Naturally 
among  a  multitude  of  forms  there  is  a  great  diversity  of  individual 
adaptations.     Thus   our  white   oak,    Quercus   alba,   is   especially 


Fig.  28.  Sketch  Map  Showing  Existing  Distribution  of  the  Beeches, 
Fagus  and  Nothofagus,  and  or  Castanopsis 


sensitive  to  excess  suppHes  of  ground  water,  whereas  the  swamp 
white  oak,  Quercus  lyrata,  the  willow  oak,  Quercus  pkellos,  and  the 
various  water  oaks  are  extremely  tolerant  of  water  and  often  live 
in  swamps  and  similar  environments  where  the  surface  may  be 
flooded  for  part  of  the  year,  and  where  it  is  always  very  wet. 

The  oaks  are  mostly  massive  trees  with  straight  trunks,  furrowed 
bark,  and  large  powerful  branches.     Some,  like  the  white  oaks, 


136  TREE    ANCESTORS 

mature  their  acoms  in  a  single  season,  and  others,  like  the  black 
and  red  oaks  require  two  years  to  mature  their  fruit.  The  pollen 
bearing  flowers  are  minute  and  are  borne  singly  on  thread-like 
pendulous  stalks  in  tassels  from  the  twigs  of  the  previous  year. 
The  seed  bearing  flowers  are  separate  from  those  which  produce 
the  pollen  and  are  also  minute,  being  borne  singly  or  in  clusters 
from  the  bases  of  the  young  growing  leaves  of  the  spring.  The 
pollen  is  brought  to  the  ovulate  flowers  through  the  agency  of  the 
wind,  and  the  mature  acoms  are  disseminated  by  being  carried  by 
streams,  to  a  slight  extent  being  blown  about  by  winds,  and  largely 
through  the  agency  of  mammals  such  as  squirrels,  or  birds.  On 
the  whole  they  spread  much  more  slowly  than  do  the  seeds  of  trees 
which  have  winged  fruits  like  so  many  of  our  forest  trees. 

There  is  but  slight  need  to  take  the  space  to  eulogize  the  virtues 
of  oak  timber,  which  have  been  recognized  for  ages.  The  different 
species  exhibit  great  diff^erences,  however,  which  lumber  dealers 
are  somewhat  prone  to  overlook.  Governments  once  maintained 
reserves  of  live  oak  timber  for  ship  building  purposes  as  today  they 
maintain  oil  reserves.  Cheap  oak  furniture  consumes  large  quanti- 
ties of  the  wood  at  all  times,  and  the  better  grades  vary  with  the 
fashions  for  flemish,  golden,  antique  and  other  classes  of  finish  or 
period  furniture.  Much  oak  goes  into  the  better  grades  of  flooring 
and  interior  finish,  and  this  inventory  merely  hints  at  the  variety 
of  uses  and  the  great  annual  consumption  of  oak  wood  for  these  and 
for  tanning,  milling,  vehicle  and  other  purposes. 

The  oaks  are  characterized  by  the  sub-epidermal  development 
of  cork  in  their  stems,  and  this  tendency  becomes  excessive  and  the 
basis  of  an  industry  in  the  case  of  the  cork  oak,  Quercus  suber 
and  its  varieties.  This  tree  of  southern  Europe  and  northern 
Africa  has  been  utilized  for  at  least  the  last  two  thousand  years 
exactly  as  it  is  at  the  present  time.  Camillus  is  said  to  have  worn 
a  cork  life  preserver  when  he  swam  the  Tiber  during  the  siege  of 
Rome  by  the  Gauls.  The  gall  oak,  Quercus  infectoria,  like  all  the 
other  oaks  produces,  but  more  abundantly,  the  tumors  due  to 
insect  injuries,  and  known  as  galls,  and  these  have  entered  ex- 
tensively into  the  manufacture  of  black  ink — less  largely  in  recent 


THE   OAK   AND    CHESTNUT  137 

chemical  years.  The  tree  is  a  native  of  Asia  Minor  and  Syria, 
Aleppo  being  the  chief  exporting  point. 

Oak  wood  is  distinguished  by  a  feature  that  it  shares  with  the 
beech,  in  that  in  both  there  are  large  compound  rays  running 
radially  through  the  wood  in  addition  to  the  small  secondary  rays, 
and  it  is  these  large  rays  that  give  the  so-called  silver  grain  to 
oak  wood. 

The  oaks  appear  to  have  diverged  from  the  ancestral  Dryophyl- 
lum  stock  at  the  dawn  of  the  Upper  Cretaceous,  or  perhaps  in  the 
closing  days  of  the  Lower  Cretaceous.  Some  hundreds  of  kinds 
of  fossil  oak  leaves  have  been  described,  but  a  considerable  num- 
ber of  these,  and  especially  those  from  the  earher  rocks  are  more 
or  less  open  to  suspicion  regarding  their  proper  identification. 
Cretaceous  oaks  have  been  described  from  both  Austraha  and  New 
Zealand,  and  Tertiary  oaks  from  Australia  and  Tasmania  by 
Ettingshausen,  but  that  acute  botanist  was  obsessed  with  the 
absolute  cosmopolitanism  of  the  Tertiary  floras,  and  most,  if  not 
all,  of  his  oak  determinations  are  not  to  be  rehed  upon.  I  do  not 
deny  the  possibility  that  oaks  may  have  formed  a  part  of  that 
ancient  flora  which  appears  to  have  spread  southeastward  from 
Asia  during  Cretaceous  times,  but  the  proof  of  this  must  await 
more  convincing  evidence  than  has  as  yet  come  to  light. 

Similarly,  only  4  of  the  14  species  of  oaks  that  Heer  described 
from  the  Cretaceous  rocks  of  western  Greenland  appear  to  be  true 
oaks.  A  large  number,  20  in  all,  of  equally  dubious  oaks  have 
been  described  from  the  Dakota  sandstone  of  our  western  states — 
this  sandstone  representing  the  initial  deposits  of  the  advancing 
Upper  Cretaceous  sea  in  that  region.  Next  in  point  of  numbers 
are  the  16  species  of  supposed  oaks  described  from  somewhat  later 
Upper  Cretaceous  deposits  in  Westphalia.  Other  Cretaceous  oaks 
have  been  recorded  from  Silesia,  Prussia,  Saxony  and  Bohemia  in 
Europe;  from  Alaska  and  Vancouver  Island  on  this  continent;  and 
from  aU  sections  of  the  United  States  where  rocks  of  this  age  are 
known,  to  a  much  larger  extent  in  the  West  than  in  the  Atlantic 
Coastal  Plain.  No  characteristic  fruits  have  been  found  with  these 
early  oak-like  leaves,  wliich,  if  they  are  true  oaks,  belong  to  the 


138  TREE   ANCESTORS 

entire  holly,  and  chestnut  oak  types,  and  may  really  represent 
varieties  of  Dryophyllum. 

There  are  many  oaks  described  from  the  Eocene  period,  some 
undoubted  in  their  identity,  and  represented  by  fruits  as  well  as 
leaves.  They  occur  in  the  basal  Eocene  of  Belgium,  and  in  the 
present  plains  country  bordering  the  Rocky  Mountains,  which, 
however  had  not  yet  been  elevated  at  the  time  that  they  flourished. 
Later  in  the  Eocene  we  find  oaks  especially  abundant  and  wide- 
spread in  far  northern  lands,  at  that  time  marked  by  milder  tem- 
peratures than  prevail  at  the  present  time,  a  time  when  temperate 
floras  pushed  toward  the  poles  and  tropical  floras  invaded  the  tem- 
perate zones.  Fifteen  different  oaks,  nearly  all  authentic  and  of 
the  chestnut  or  holly  oak  type  are  recorded  from  the  late  Eocene 
deposits  of  western  Greenland:  6  are  recorded  from  Alaska: 
3  from  Sachalin  Island:  4  or  5  from  British  Columbia:  1  from 
Iceland:  and  5  from  Spitzbergen. 

Oiigocene  times,  largely  unrepresented  by  plant  bearing  beds 
in  North  America,  show  numerous  oaks  in  Russia,  Germany,  France 
and  Italy.  Oaks  are  exceedingly  abundant  everywhere  through- 
out the  northern  hemisphere  during  Miocene  times,  especially  in 
the  humid  forested  Mediterranean  countries  and  those  of  our 
Pacific  coast  region,  in  both  of  which  many  noble  oak  forests  must 
have  dehghted  ancestral  squirrels  and  extinct  members  of  the  swine 
family  with  their  bounty.  Thus  33  Miocene  oaks  have  been  re- 
corded from  Italy  alone,  20  from  France,  15  from  Switzerland,  12 
from  Hungary  and  Croatia,  13  from  Styria,  10  from  Baden,  9 
from  Bohemia,  7  from  Spain  and  Greece.  In  this  country  the 
records  include  Virginia  on  the  East  coast,  Oregon  and  California 
on  the  West  coast,  the  two 'last  with  more  than  10  species  each. 
Nevada,  Idaho  and  the  Yellowstone  Park  all  furnish  their  Miocene 
oaks,  and  the  forested  lake  shores  of  the  Miocene  mountain  basin 
of  Florissant  in  the  Colorado  Rockies  furnish  us  with  a  dozen 
species  of  oaks  along  with  numerous  other  plant  and  insect  types 
preserved  in  contemporaneous  showers  of  volcanic  ashes. 

Phocene  times  carry  on  the  Miocene  forests  which  were  slowly 
changing.     Over  30  oaks  have  been  described  from  deposits  of 


THE    OAK   AND   CHESTNUT  139 

this  age  in  Italy,  and  France  had  nearly  as  many.  Southern  Spain 
has  furnished  a  dozen  species,  and  others  are  scattered  through 
Germany,  Styria,  Slavonia  and  Asia  Minor,  to  the  Altai  Mountains 
of  central  Asia,  and  to  Japan  and  Indo-China — the  two  last  regions 
each  furnishing  6  species.  In  this  country  PHocene  plant  bearing 
deposits  are  much  rarer,  but  2  oaks  have  been  recorded  from  New 
Jersey.  Four,  including  an  ancestral  live  oak,  are  found  in  Ala- 
bama, and  a  form  like  the  modern  Quercus  chrysolepis  has  been 
described  from  California. 

Many  oaks  have  been  recorded  from  the  Pleistocene,  found  in 
deposits  of  Inter-  or  Post-Glacial  age.  Naturally  these  are  largely 
representatives  of  still  existing  species.  Of  between  20  and  30 
of  the  Pleistocene  forms  recorded,  only  3  or  4  are  extinct,  and 
several  of  these  such  as  pseudoalba  or  predigitata  are  but  doubt- 
fully extinct.  With  the  exception  of  3  oaks  from  the  interesting 
Interglacial  deposits  of  the  Don  valley  near  Toronto  the  bulk  of 
the  American  records  have  come  from  the  Coastal  Plain  in  New 
Jersey,  Maryland,  Virginia,  North  Carolina,  Florida,  Alabama, 
Mississippi,  Tennessee  and  Kentucky.  Oaks  occur  also  in  the 
Pleistocene  terraces  near  Morgantown,  West  Virginia,  and  in  cave 
deposits  in  Pennsylvania. 

There  is  an  early  Pleistocene  oak  found  in  the  same  deposits  that 
yielded  the  bones  of  the  Ape  man,  Pithecanthropus,  on  the  Island 
of  Java,  and  several  still  existing  European  oaks  have  been  dis- 
covered in  the  Pleistocene  of  Denmark,  Germany,  France,  Italy 
and  Hungary. 

Opinions  differ  regarding  the  relationships  of  these  numerous 
fossil  and  living  oaks.  Ettingshausen  saw  in  the  Tertiary  holly 
oak,  Quercus  palaeo-ilex,  a  synthetic  t3rpe  from  which  many  of  the 
existing  forms  might  have  been  derived,  and  Trelease  regards  our 
existing  western  Quercus  chrysolepsis  as  representative  of  a  similar 
synthetic  type.  The  latter  author  sees  no  evidence  of- close  rela- 
tionsliip  between  American  and  European  Tertiary  species,  but 
thinks  that  there  was  an  entirely  independent  evolution  in  both 
hemispheres.  This  is  inherently  improbable,  and  although  simi- 
larities in  fohar  characters  which  can  be  pointed  out  are  necessarily 


140  TREE    ANCESTORS 

inconclusive,  so  many  other  genera  show  beyond  question  that 
there  was  a  close  filiation  between  the  forms  of  the  different  north- 
em  continents,  that  it  seems  that  the  oaks  could  not  be  an  ex- 
ception to  this  general  history,  although  it  is  very  doubtful  if  there 
was  any  possibility  of  an  interchange  of  species  between  the  Old 
and  New  Worlds  after  late  Eocene  or  Ohgoccnc  times. 

THE    CHESTNUT 

The  scientific  name  of  the  genus  to  which  the  chestnut  belongs 
is  Castanea,  derived  from  the  town  of  Castane  in  Thessaly,  once 
famous  for  its  chestnuts.  The  common  name  is  said  to  be  derived 
from  the  fact  that  the  nuts  are  borne  in  an  enclosed  box  or  chest. 
Five  existing  species  are  recognized.  The  most  famihar  of  t/icse 
is  the  common  European  Spanish,  or  sweet  chestnut  as  distinct 
from  the  horse-chestnut,  which  belongs  to  a  totally  different  family 
of  trees.  This  so-called  Spanish  chestnut,  so  named  because  most 
of  the  commercial  supplies  were  formerly  shipped  from  Spain,  is 
often  called  the  Italian  chestnut  in  this  country  for  the  same  reason. 
It  is  a  magnihcent  tree,  indigenous  in  Mediterranean  countries 
from  Portugal  to  Persia.  Rumor  places  its  home  in  the  Pontus 
region  and  goes  on  to  relate  that  the  Emperor  Tiberius  introduced 
it  into  Italy  from  Asia  Minor  and  that  it  spread  from  thence  over 
southern  Europe.  Since  it  occurs  fossil  in  France  and  Spain 
before  the  Pleistocene  glaciation,  and  is  found  in  the  Interglacial 
deposits  of  Italy  before  the  men  of  the  Old  Stone  Age  are  known 
to  have  arrived  in  that  country,  the  traditions  mentioned  above 
are  conclusively  disproved. 

It  is  a  most  imposing  and  stately  tree,  attaining  a  very  great 
size,  and  many  large  trees  are  on  record.  The  most  celebrated  of 
these  is  the  Castagno  di  cento  cavalli,  or  tree  under  which  100  horse- 
men once  took  refuge,  growing  on  the  slopes  of  Mount  Etna,  and 
which,  according  to  the  measurements  of  Count  Borch  made  in 
1780,  had  a  circumference  of  190  feet.  The  Tortworth  chestnut, 
said  to  have  been  a  boundary  tree  in  the  time  of  King  John,  was 
still  standing  in  1788.     At  5  feet  from  the  ground  it  is  said  to  have 


THE   OAK   AND   CHESTNUT 


141 


been  50  feet  in  circumference,  although  the  tree  is  not  a  native  of 
Britain.  Much  attention  has  been  given  to  its  culture  in  Europe 
and  many  varieties  have  consequently  originated.  The  very  large 
nuts,  otherwise  like  those  of  our  American  tree,  are  a  staple  article 
of  food  in  south  Europe  and  the  Levant,  particularly  among  the 
poorer  classes,  being  eaten  raw,  boiled  or  roasted.     The  nuts  are 


Fig.  29.  Sketch  Map  Showing  Existing  Range  (solid  black)  and  the 
Fossil  Occurrences  (solid  circles)  of  the  Chestnut 


also  dried  and  made  into  flour,  and  there  is  a  considerable  export 
trade  in  them  from  Spain  and  Italy.  Botanists  formerly  called 
the  tree  Castanea  vesca  from  the  Latin  vescor,  i.e.,  to  eat,  but  the 
accepted  modem  name  is  Castanea  vulgaris,  or  common  chestnut. 
It  was  formerly  confused  with  the  Japanese  Castanea  japonica, 
of  limited  distribution  in  eastern  Asia,  and  with  the  common 


142 


TREE   ANCESTORS 


American  chestnut  or  Castanea  americana,  now  known  as  Castanea 
dentata,  from  the  shape  of  its  leaves.  We  have  two  additional 
chestnuts  in  southeastern  Xorth  America — the  Chinquapin  or 
Castanea  piimila,  which  ranges  from  southern  Pennsylvania  to 
northern  Florida  and  eastern  Texas,  and  the  shrubby  Castanea 
nana  of  the  southern  States. 


Fig.  30.  Sketch  Map  Showing  Distribution  of  the  Existing  Genus 
Pasania  and  the  Extinct  Genus  Dryophyllum 


Our  common  and  better  known  American  tree,  which  ranges  from 
southern  Maine  to  Michigan  and  in  the  Appalachian  uplands  to 
Alabama  and  Mississippi,  has  never  been  cultivated  like  its  Euro- 
pean relative  except  for  ornamental  planting  in  grounds  and 
parks.  In  recent  years  the  chestnut  blight  has  been  sweeping  its 
range,  and  the  rising  generation  will  scarcely  know  its  beauty  or  the 


THE    OAK  AND    CHESTNUT  143 

excellence  of  its  fruit,  which  in  flavor  greatly  surpasses  that  of  the 
Old  World  tree.  It  seems  probable,  however,  that  the  shoots 
from  old  stumps  or  present  day  seedhngs  will  grow  into  trees  with 
more  or  less  immunity  to  the  bhght,  and  that  the  species  will  not 
become  entirely  extinct. 

The  wood  of  all  of  the  chestnuts  is  coarse  grained,  and  not  to 
■be  compared  with  the  better  kinds  of  oak.  In  an  old  English  work 
on  trees  we  read  "The  chestnut  is  of  Httle  value  for  timber."  The 
wood  is  hght  and  soft  and  liable  to  check  and  warp.  It  contains 
much  tannin  and  is  consequently  very  durable  in  contact  with 
the  soil,  and  was  hence  much  used  for  posts,  cross  ties,  etc.  The 
blight  has  caused  large  quantities  to  be  cut  and  used  as  fuel. 
Burned  in  the  grate  it  crackles  and  throws  sparks,  but  is  very 
cheery  and  satisfactory  if  screened, 

Nonnally  the  tree  reached  a  height  of  about  100  feet,  and  a 
trunk  diameter  of  3  or  4  feet,  and  occasionally  of  10  to  12  feet. 
It  is  said  by  Sargent  to  reach  its  largest  size  in  the  Great  Smoky 
Mountain  region  of  western  North  Carolina  and  eastern  Tennessee. 
The  leaves  are  similar  to  those  of  some  of  the  oaks,  but  preserve 
the  ancestral  Dryophyllum  form  much  better  than  most  of  the 
living  members  of  the  family.  They  are  also  not  so  varied  in  the 
past  as  were  the  oaks,  which  is  natural  enough  since  the  latter  are 
still  a  more  varied  and  vigorous  stock,  and  one  which  has  repeatedly 
passed  through  periods  of  evolutionary  activity  in  the  past. 

A  species  of  chestnut  has  been  described  from  the  Upper  Creta- 
ceous of  Saxony,  but  it  is  probably  a  Dryophyllum,  as  are  several 
of  the  supposed  chestnuts  from  the  Eocene,  notably  those  recorded 
from  western  Greenland.  There  are,  however,  several  undoubted 
chestnuts  found  in  the  Eocene  in  North  America,  France  and 
Italy.  Six  or  8  have  been  described  but  there  remains  great  un- 
certainty regarding  their  specific  limits.  The  Oligocene  has 
furnished  the  remains  of  4  species  in  southern  Europe.  Thirteen 
nominal  species  have  been  recorded  from  Miocene  deposits.  The 
leaves,  and  in  some  cases  the  fruits,  have  been  found  fossil  in  beds 
of  this  age  in  France,  Germany,  Italy,  Silesia,  Styria,  Croatia, 
Carinthia,  Austria,  Hungary,  Transylvania,  and  Gahcia  injEurope. 


144  TREE    ANCESTORS 

In  Japan  in  Asia;  and  in  Colorado,  Yellowstone  Park,  and  Oregon 
in  this  country.  The  Phocene  records  comprise  the  remains  of  1 1 
nominal  species,  found  in  Spain,  France,  Germany,  Italy,  Styria 
and  Slavonia  in  Europe:  in  Asia  Minor,  Japan  and  Indo-China  in 
Asia:  and  in  New  Jersey  in  this  country. 

The  modem  species  represent  the  survivors  from  these  Pliocene 
forms  which  did  not  succumb  to  the  rigors  of  the  Pleistocene  gla- 
ciations.  The  European  chestnut  is  found  in  the  Interglacial 
deposits  in  France  and  Italy,  and  our  American  chinquapin  has 
been  found  fossil  in  deposits  of  Pleistocene  age  in  West  Virginia, 
Kentucky  and  Tennessee. 

Some  of  the  more  interesting  forms  of  leaves  of  fossil  and  recent 
oaks  are  shown  on  the  accompanying  plate,  and  the  small  sketch 
maps  summarize,  not  only  the  distribution  of  the  oaks  and  chest- 
nuts, but  of  the  other  genera  as  well,  of  this  interesting  and  most 
important  family  of  trees. 

Fig.  31.  Some  Recent  and  Extinct  Oak  Leaves  (About  |  Natural  Size) 

1.  Dryophyllum  curticellense  Sap.  &  Marion,  from  the  Paleocene  of  Belgium. 

2.  Dryophyllum  levalense  Marty,  from  the  same  horizon  and  region. 
3-5.  Quercus  chrysolepis  Lieb.  a  living  s}'nthetic  type. 

6.  Quercus  serrata  Thunb.,  a  living  Oriental  type. 

7,  8.  Quercus  ilex  Linne,  an  Old  World  synthetic  type. 

9.  Quercus  oligodonta  Saporta,  from  the  Miocene  of  southeastern  France. 

10.  Querents  armata  Saporta,  same  locality  and  horizon. 

11.  Quercus  confer ta  Kit.,  a  living  species. 

12.  Quercus  ursma  Knowlton,  a  Miocene  black  oak  from  Oregon. 

13.  Quercus  imhricaria  Michx.,  a  living  entire  leafed  form. 

14.  Quercus  ilicijolia  Wagenh.,  a  living  species. 

15.  Quercus  Chapmanifoliu,  Berry,  A  Pliocene  oak  from  Alabama. 

16.  Quercus  concinna  Wagenh.     A  living  species. 

17.  Quercus  lobbii  Hook,  f.,  a  modern  Asiatic  form. 


THE   OAX   AND    CHESTNUT 


145 


Fig.  31 


CHAPTER  XIV 

The  Elm,  Planer  and  Hackberry 

The  elm  family  is  known  scientifically  as  the  Ulmaceae,  the  name 
being  derived  from  the  Latin  Ulmus,  which  was  the  classical  name 
of  the  European  elm,  said  to  have  been  derived  from  the  Celtic 
elm.  Like  so  many  other  tree  famihes  the  elm  family  offers  much 
of  interest  to  students  of  geographical  distribution  and  its  bearing 
upon  geological  history.  Strange  as  it  may  seem  to  those  who  know 
only  our  familiar  elms  of  the  shaded  malls  and  streets  of  our  New 
England  towns,  the  elm  family  is  a  largely  tropical  group,  although 
the  elms  themselves  are  inhabitants  of  the  Temperate  Zone  except 
for  their  occurrence  in  the  mountains  of  tropical  Asia. 

The  family  contains  about  15  genera  and  considerably  over  150 
species,  of  which  less  than  one  half  belong  to  the  elms  and  hack- 
berries,  which,  with  the  single  unique  planer  tree  of  our  southeast- 
em  States,  are  the  only  members  of  the  family  native  in  the  United 
States.  To  the  botanist  the  problem  of  the  absence  of  elms  and 
hackberries  and  the  presence  of  3  other  genera  in  Africa  is 
difficult  to  explain,  as  is  the  absence  of  elms  and  true  hackberries 
in  South  America  where  there  are  four  other  genera  of  the  family 
represented.  A  similar  unsolved  problem  is  the  range  of  the  genus 
Solenostigma  from  the  Mascarene  Islands  to  Polynesia  and  its 
absence  in  Africa,  or  the  presence  of  Zelkova  in  Asia  Minor  and 
the  Caucasus  and  its  reappearance  in  northeastern  China  and 
Japan ;  or  why  the  hackberries  range  from  the  Atlantic  to  the  Pacific 
in  the  United  States  when  the  equally  ancient  elms  are  not  found 
in  our  west.  Many  facts  pointing  toward  the  solution  of  these 
problems  have  been  derived  from  the  study  of  fossil  plants,  but 
unfortunately  no  traces  of  many  of  the  genera  of  the  elm  family 
have  as  yet  been  found  in  the  rocks.  For  example  a  genus  like 
Trema  found  at  the  present  time  in  Africa,  Asia,  Austraha  and 
South  America  e\ddently  had  a  long  geological  history  since  it 

146 


THE  ELM,  PLANER  AND  HACKBERRY  147 

could  not  attain  such  a  distribution  in  the  world  of  today,  but 
absolutely  nothing  is  known  of  its  geological  history. 

The  family  splits  sharply  into  two  groups:  those  in  which  the 
fruit  is  dry  and  winged,  as  in  the  elms,  and  is  distributed  by  the 
wind;  and  the  other  in  which  the  fruit  is  more  or  less  pulpy,  or  a 
drupe,  with  a  bony  stone,  and  is  distributed  by  birds  and  mammals, 
as  in  the  hackberry — the  flesh  being  the  attraction,  and  the  stone 
with  its  contained  seed  passing  uninjured  through  their  alimentary 
tract,  and  discharged  properly  fertihzed,  often  at  a  great  distance 
from  the  parent  tree.  The  winged  fruits  of  the  common  elm,  as 
everyone  knows,  mature  in  the  spring  and  are  immediately  shed, 
usually  sprouting  the  same  season,  whereas  the  hackberry  fruits 
ripen  in  the  autumn  and  do  not  sprout  until  the  following  season. 

All  three  of  the  types  of  trees  to  which  this  chapter  is  devoted 
have  their  chief  utility  as  shade  trees,  although  one  of  the  hack- 
berries  is  useful  in  many  other  ways  when  planted  in  our  semi  arid 
plains  country,  and  some  are  extensively  lumbered  in  some  regions. 
Their  chief  blessing  may  be  said  then  to  be  largely  aesthetic.  One 
cannot  observe  a  row  of  elms  without  being  impressed  with  the 
beauty  of  trees  and  how  poor  the  world  would  be  without  them, 
and  if  it  is  true,  as  some  botanists  assert,  that  the  herbaceous  plants 
are  more  efficient  than  trees  and  will  as  time  goes  on  gradually 
replace  the  forests,  we  can  rejoice  that  this  process  will  require 
milHons  of  years.  I  suspect  that  if  we  lived  in  an  arid  region  we 
would  venerate  the  trees  as  the  Arab  does  the  palm;  certainly  I 
know  nothing  so  attractive  as  forests  after  one  has  spent  a  few 
months  in  a  desert.  The  wood  of  both  the  elm  and  the  hackberry 
is  marked  by  wavy  or  zigzag  lines  of  minute  pores  when  viewed  in 
cross  sections  of  the  trunk,  a  character  not  seen  in  the  wood  of  any 
other  of  our  forest  trees. 

THE    ELMS 

Elms  are  widely  distributed  throughout  the  North  Temperate 
Zone,  except  in  western  North  America.  They  extend  southward 
as  far  as  Mexico  in  the  New,  and  to  the  Sikkim  Himalayas  in  the 
Old  World,  both  of  these  occurrences  at  the  southern  limit  of 


JM\A   A        l,iJ3i»A 


Jft  C  State  College 


148  TREE   ANCESTORS 

range  being  probably  clue  to  their  southward  spread  caused  by  the 
less  genial  conditions  that  prevailed  during  the  glacial  period  in 
the  northern  lands,  for  although  the  genus  may  have  been  originally 
of  tropical  ancestry  that  far  off  event  was  long  antecedent  to  Pleisto- 
cene times. 

The  common  European  elm,  Ulmiis  campestris,  is  a  doubtful 
native  of  England,  and  is  said  to  have  been  introduced  by  the 
Romans.  This  is  rendered  probable  by  the  fact  that  it  rarely 
perfects  its  seeds  there.  Before  the  employment  of  cast  iron  its 
wood  was  in  much  demand  for  water  pipes,  since  it  is  remarkably 
durable  under  constant  conditions  of  either  wetness  or  dryness, 
although  decaying  readily  upon  exposure  to  weather.  Its  inner 
bark  was  formerly  much  used  for  mats  and  ropes,  and  also  in 
medicine,  although  it  contains  much  less  mucilage  than  our  familiar 
slippery  elm. 

Few  trees  are  more  imposing  or  more  graceful  when  planted  in 
avenues.  Francis  I  is  said  to  have  inaugurated  this  practise 
in  France,  and  it  subsequently  became  a  sort  of  English  tradi- 
tion, especially  in  New  England.  The  Long  Walk  at  Windsor  is 
bordered  by  elms,  and  magnificent  examples  are  to  be  found  in  all 
the  older  towns  of  New  England.  The  Concord  Elm  is  one  of  the 
New  England  elms  celebrated  in  colonial  history,  and  there  was  a 
fine  old  elm  on  Boston  Common  measuring  22  feet  in  circumference 
which  was  destroyed  by  a  storm  in  1876. 

The  Scotch  or  Wych  elm,  Ulmus  montana,  is  indigenous  in  Brit- 
ain, and  is  the  common  elm  in  Scotland.  It  is  a  much  smaller 
as  well  as  a  hardier  tree  than  Ulmus  campestris,  and  carries  the 
northern  limit  of  the  elms  northward  to  latitude  67°  in  Europe, 
or  4  degrees  beyond  the  range  of  the  common  European  elm.  Its 
twigs  were  formerly  much  used  for  divining  purposes.  The  highly 
ornamental  weeping  elm  is  a  horticultural  variety  of  this  species. 

We  have  6  native  elms  in  North  America,  the  white  or  American 
elm,  Ulmus  americana,  being  the  largest,  and  fully  the  equal  of 
the  European  elm  in  both  size  and  gracefulness,  and  like  it,  much 
planted  as  a  shade  tree  in  our  northern  States,  and  more  rarely  in 
western  and  northern  Europe.     It  grows  naturally  from  southern 


THE    ELM,    PLANER    AND    IIACKBERRY  149 

Newfoundland  and  the  Great  Lakes  to  the  foothills  of  the  Rockies, 
and  southward  to  Florida,  being  smaller  toward  its  southern  limits 
and  confined  to  stream  banks  in  the  prairie  States. 

The  rock  or  cork  elm,  Ulmus  racemosa,  is  a  northern  form  with  a 
corky  bark,  of  our  northern  states  and  southern  Canada;  and  the 
Wahoo  or  winged  elm,  Ulmus  alata,  is  a  similar  corky  species  of 
our  southern  states,  in  which  it  is  frequently  planted  as  a  shade 
tree.  The  red  or  slippery  elm,  Ulmus  fulva,  is  famihar  to  every 
rural  boy  of  our  eastern  states  because  of  its  thick  fragrant  inner 
bark,  which  is  very  mucilaginous  and  affords  dehghtful  chewing 
in  the  spring  time  when  the  sap  is  flowing.  It  is  used  to  som^e 
extent  in  medicine  as  a  demulcent  for  inflammatory  affections. 

Our  tv/o  other  American  elms — the  cedar  elm,  Ulmus  crassifolia, 
and  the  red  elm,  Ulmus  serotina,  differ  from  the  others  in  flowering 
in  the  autmnn  instead  of  the  spring,  a  habit  correlated  with  their 
southern  range.  They  are  both  fair  sized  trees  occasionally  planted 
as  shade  trees  in  Texas,  Alabama  and  Georgia,  and  with  restricted 
natural  ranges  in  that  general  region.  They  will  be  unfamiliar  to 
most  of  my  readers. 

A  large  number  of  fossil  elms  have  been  described  and  a  few  of 
these  have  been  reproduced  in  the  accompanying  figures.  It  is 
not  always  possible  to  distinguish  with  certainty  between  elms  and 
hornbeams  or  iron-wood  when  the  leaves  only  are  preserved  as 
fossils.  There  is  no  positive  evidence  of  the  presence  of  elms  in 
the  forests  of  Upper  Cretaceous  times  and  elms  are  thus  somewhat 
later  in  appearing  in  the  geological  record  than  are  the  ancestors 
of  the  related  planer  tree,  or  than  are  the  ancestors  of  many  of 
our  other  forest  trees.  The  name  Ulmus  has  been  applied  to 
fossils  from  the  Upper  Cretaceous  rocks  of  western  Canada,  but 
these  are  not  recognized  as  true  elms.  That  ancestral  elms  were 
already  in  existence  somewhere  during  Upper  Cretaceous  time  is 
rendered  almost  certain  by  their  abundance  and  wide  distribution 
in  the  rocks  of  the  early  Tertiary,  or  Eocene. 

Twenty-eight  Eocene  elms  have  been  described.  Several  of 
these  are  from  the  earhest  deposits  of  that  time,  often  called 
Paleocene,  and  the  reason  that  we  think  that  the  ancestral  stock 


150  TREE    ANCESTORS 

went  back  much  farther  than  the  geological  records  indicate  is 
the  presence  of  several  elms  in  the  basal  Eocene  of  such  widely 
separated  regions  as  France  and  Colorado.  Presumptively  these 
ancient  elms  reached  these  localities  from  a  third  and  more  northern 
area.  None  are  known,  however,  from  the  Upper  Cretaceous  plant 
beds  of  western  Greenland  where  so  many  ancestral  forms  have 
been  found,  so  that  we  cannot  be  sure  whether  the  ancestral  elms 
spread  to  France  across  an  Upper  Cretaceous  North  Atlantic 
land  bridge  or  whether  Asia  was  their  original  home  and  that  they 
spread  from  that  continent  southwestward  into  western  Europe 
and  southeastward  across  the  Behring  Sea  land  bridge  into  the 
western  land  mass  of  North  America  which  was  separated  at  that 
time  from  eastern  North  America  by  an  inland  sea. 

Later  in  Eocene  time,  with  the  spreading  of  the  seas  and  the 
opening  up  of  the  Arctic  to  a  free  oceanic  circulation  from  low 
latitudes,  the  elms,  along  with  so  many  of  our  temperate  forest 
types,  spread  into  the  far  northern  lands,  and  late  Eocene  elms 
are  recorded  from  Colorado,  Wyoming,  Montana  and  Oregon 
northward  through  British  Columbia,  where  seven  species  have 
been  found,  to  Alaska,  and  across  the  north  Pacific  in  beds  of  this 

Fig.  32.  Some  Recent  and  Fossil  Elms  and  Hackberries  (About  § 
Natural  Size) 

1.  Ulnius  Montana  Sm.,  the  Witch  Elm,  leaf.     2.  Fruit. 

3.  Ulmus  fulva  Michx.,  the  Slippery  Elm,  leaf.     4.  Fruit. 

5.  Ulmus  alata  Mich.x.,  the  Winged  Elm,  leaf.     6.  Fruit. 

7.  Ulmus  plurinervia  Unger,  a  Miocene  elm  leaf.     8.  Fruit. 

9.  Ulmus  bicornis  Unger,  a  fossil  elm  fruit. 

10.  L7wm5  5ro?nzfi  Unger,  a  Miocene  elm  fruit.     11.  A  leaf. 

12.  Ulmus  longifolia  Velen.,  a  Miocene  fruit. 

13.  Ulmus  prisca  Unger,  another  Miocene  fruit. 

14.  Ulmus  Braunii  Heer,  a  Miocene  leaf. 

15.  Celtis  australis  L.,  fruit.     16.  Leaf. 

17.  Celtis  japonica  Pr.,  leaf. 

18.  Celtis  Hyperionis  Unger,  a  Miocene  stone. 

19.  Celtis  Japcti  Unger,  a  JSIiocene  leaf. 

20.  Celtis  occidentalis  L.  The  American  Hackberry,  leaves  and  fruit. 

21.  Celtis  Bernhardtii  Klotzsch,  a  leaf. 


152  TREE   ANCESTORS 

same  age  on  Sachalin  Island.  They  were  also  present  at  that  time 
in  Grinnell  Land,  Iceland  and  Spitzbcrgen. 

As  usual  with  all  tree  histories  the  Oligocene  records  show  a  fall- 
ing off  in  abundance  and  variety  of  elms,  only  4  being  known 
from  rocks  of  that  age  and  these  being  confmed  to  the  European 
area,  where  they  are  found  in  France,  Italy,  Germany  and  Styria. 
If  the  Oligocene  record  is  poor  that  of  the  succeeding  Miocene  rocks 
fully  make  up  for  this  paucity  of  records  for  the  closing  days  of  the 
older  Tertiary,  for  we  know  over  30  Miocene  species  of  elms,  and 
they  were  very  abundant  at  many  localities,  particularly  in  Europe. 
Elms  must  have  been  a  prominent  element  in  the  Miocene  forests 
of  Europe  for  their  remains  occur  in  rocks  of  that  age  in  the  follow- 
ing countries:  France,  Switzerland,  Italy,  Germany,  Bohemia, 
Silesia,  Styria,  Carinthia,  Croatia,  Gahcia,  Austria,  Hungary, 
Transylvania  and  the  Caucasus.  In  Asia  3  species  have  been 
found  in  the  late  Miocene  of  Japan.  In  North  America  they 
occur  on  both  the  east  and  west  coasts  and  in  the  interior,  being 
knouTi  from  Maryland,  Virginia,  Florida,  Mississippi,  Colorado, 
Oregon  and  California.  They  were  not  uncommon  at  that  time  in 
the  basin  in  which  lay  the  Miocene  Lake  Florissant  in  the  Colorado 
Rockies,  and  their  occurrence  in  the  early  Miocene  deposits  of 
Florida  and  Mississippi  is  especially  interesting  because  there  they 
were  associated  with  breadfruit,  palms,  and  other  warm  climate 
types  of  trees. 

The  Miocene  probably  witnessed  the  maximum  distribution  of 
the  elms,  for  at  that  time  they  flourished  in  regions  from  which 
they  are  absent  in  modem  times.  During  the  succeeding  Pliocene 
about  a  score  of  species  of  elms  contributed  to  the  geological  record. 
They  were  especially  abundant  in  southern  Europe,  in  Spain, 
France,  Italy,  Germany,  Styria  and  Slavonia.  They  were  repre- 
sented in  the  Pliocene  deposits  of  Asia  Minor,  and  the  far  east  had 
its  species  in  Japan.  American  records  are  as  usual  for  the  PHo- 
cene,  scanty,  but  two  elms  of  that  age  are  known  from  southern 
New  Jersey. 

Pleistocene  climatic  changes  and  the  glaciation  of  that  time  un- 
doubtedly played  their  parts  in  bringing  about  the  modem  dis- 


THE    ELM,    PLANER    AND    HACKBERRY  153 

tribution  of  the  elms,  but  we  are  ignorant  of  the  details  during  that 
dramatic  period  of  earth  history.  Eight  different  species  of  elm 
have  been  found  in  Pleistocene  deposits.  Most  of  these  represent 
species  that  still  exist,  but  supposed  extinct  forms  have  been  de- 
scribed from  England  and  Maryland.  The  common  European 
elm,  Ulmus  campestris,  has  been  found  fossil  in  France,  Italy  and 
Crimea.  Our  common  American  elm,  Ulmus  amsricana,  occurs  in 
the  Pleistocene  in  Maryland  and  in  interglacial  deposits  of  Ontario. 
Our  southern  winged  elm  or  wahoo,  Ulmus  alata,  has  been  found 
fossil  in  North  Carolina,  Alabama  and  Kentucky;  and  the  northern 
cork  or  rock  elm,  Ulmus  racemosa,  is  present  in  the  Pleistocene 
river  terraces  near  Morgantown,  West  Virginia,  and  in  the  inter- 
glacial beds  of  the  Don  Valley  near  Toronto. 

THE    PLANER    TREE 

The  planer  tree  or  water  elm  belongs  to  a  genus  known  as  Planera 
and  named  in  honor  of  Johann  Jacob  Planer,  a  German  physician 
and  botanist  of  the  eighteenth  century.  Specifically  the  single 
living  species  is  known  as  aquatica  in  allusion  to  its  most  common 
habitat  in  wet  swamps.  It  is  a  small  tree,  with  a  short  trunk  rarely 
if  ever  reaching  2  feet  in  diameter,  with  slender  spreading  branches 
forming  a  low  broad  head,  and  light  soft  wood  of  no  particular 
value.  It  IS  found  at  the  present  time  from  North  Carolina  south- 
ward to  and  along  the  Gulf  Coast  as  far  as  the  Trinity  River  in 
Texas,  and  reaches  its  largest  size  in  the  swamps  of  Louisiana  and 
southern  Arkansas.  It  is  the  sole  living  representative  of  the 
genus  and  it  is  probably  becoming  gradually  more  restricted  in 
range  since  it  formerly  reached  farther  northward,  being  found 
in  Maryland  and  Kentucky  during  the  late  Pleistocene.  Its 
leaves  are  distinguishable  with  difficulty  from  those  of  some  of  the 
ehns,  and  considerable  uncertainty  pertains  to  the  determination 
of  some  of  the  earlier  species. 

Four  species  of  these  trees  have  been  recorded  from  the  Upper 
Cretaceous,  and  all  of  these  come  from  the  Western  Hemisphere 
where  they  are  found  in  Greenland,  and  in  what  is  now  the  Atlantic 
Coastal  Plain  from  Marthas  Vineyard,  New  Jersey  and  North 


154  TREE   .\NCESTORS 

Carolina.  Five  Eocene  species  have  been  described,  and  with 
the  exception  of  1  from  Mississippi  and  2  from  Wyoming  and 
North  Dakota,  these  all  belong  to  the  middle  and  upper  part  of 
the  Eocene.  Two  were  found  in  the  Green  River  basin  deposits 
and  the  balance  occur  in  those  temperate  forests  which  ranged  so 
far  to  the  northward  during  the  late  Eocene,  and  these  last  records 
of  ancestral  water  elms  include  Greenland,  Iceland,  Alaska,  Man- 
churia and  Sachalin  Island. 

A  single  OKgocene  form  is  known  from  Italy  and  Saxony.  Two 
nominal  Miocene  species  had  a  very  wide  range  and  have  been 
found  in  beds  of  that  age  all  over  southern  Europe  from  France  to 
Greece,  in  Japan,  and  in  Virginia,  Colorado  and  Oregon.  The 
water  elms  were  e\adently  not  yet  reduced  in  numbers  or  range 
in  the  later  days  of  the  Tertiary,  or  PHocene  time,  for  we  find  3 
forms  represented  in  France,  Italy,  Germany,  Styria,  and  Slavonia; 
in  New  Jersey  on  our  east  coast;  and  in  the  Altai  Mountains  of 
central  Asia.  Then  came  the  Pleistocene  with  its  glaciations  which 
seems  to  have  effectually  exterminated  these  trees  in  Asia,  unless 
indeed  their  geologic  record  on  that  continent  represent  wrong 
identifications  of  what  were  really  fossil  leaves  of  some  species  of 
the  alHed  genus  Zelkova.  A  single  form  appears  to  have  survived 
into  the  Pleistocene  of  Italy,  but  there  are  none  in  modem  Europe. 
North  American  Pleistocene  records  of  these  trees  include  Mary- 
land, North  Carolina,  Kentucky  and  Alabama. 

THE    HACKBERRIES 

The  hackberries  as  delimited  in  recent  American  botanical 
practice  comprise  a  small  group  of  large  or  medium  sized  trees, 
and  shrubs,  of  ancient  origin,  and  represented  at  the  present  time 
in  both  the  eastern  and  the  western  United  States,  and  in  eastern 
Asia.  The  question  whether  the  closely  allied  forms  of  lower  lati- 
tudes should  be  referred  to  the  same  genus  is  a  disputed  one.  They 
are  evidently  very  near  of  kin,  and  if  all  are  grouped  under  the 
generic  name  of  Celtis,  the  scientific  designation  of  the  group  to 
which  the  hackberries  belong,  and  derived  from  a  name  that  PHny 
used  for  an  African  lotus-tree,  then  this  genus  has  between  80  and 


THE   ELM,   PLANER   AND   HACKBERRY  155 

100  existing  species  and  is  common  in  the  Indo-Malayan  region,  in 
the  islands  of  Oceanica,  in  Africa,  and  in  tropical  and  sub-tropical 
America  southward  to  the  northern  Argentine. 

The  North  American  forms  to  which  alone  our  attention  will 
be  confined  number  about  9,  although  the  leaves  of  these  trees 
differ  so  much  in  size,  texture  and  character  of  the  marginal  teeth ; 
and  the  berries  vary  so  much  in  color  and  size,  that  a  number  of 
varieties  have  been  described,  and  there  is  some  uncertainty  as  to 
just  how  many  species  are  represented. 

The  most  widespread  of  our  American  forms  is  the  hackberry 
or  sugarberry,  Celtis  occidentalis ,  sometimes  called  the  nettle  tree 
from  the  resemblance  of  its  leaves  to  those  of  the  nettle.  It 
varies  in  size  according  to  its  environment  from  a  large  tree  130 
feet  tall  and  with  a  trunk  3  feet  in  diameter,  and  free  of  branches 
for  70  or  80  feet  above  the  ground,  to  a  small  tree  or  shrub  toward 
its  western  limit  of  range.  It  is  found  from  the  St.  Lawrence  River 
near  Montreal  and  Massachusetts  Bay  to  Nebraska,  Idaho  and 
eastern  Washington  and  Oregon  to  Puget  Sound.  Southward 
it  extends  down  the  Florida  peninsula  to  Biscayne  Bay  and  Cape 
Romano,  and  to  eastern  Texas. 

Its  cherry-like  fruits  have  a  sweet  thin  dry  pulp  covering  the 
stone,  and  are  greedily  eaten  by  birds,  which  thus  disseminate  the 
seeds  far  and  wide.  Flood  waters  also  occasionally  serve  the  same 
purpose.  The  wood  is  rather  heavy  and  brittle,  and  of  sHght  com- 
mercial importance.  It  is  more  or  less  lumbered  in  the  east  where 
the  trees  reach  a  large  size,  and  is  sawed  into  second  class  timber. 
It  makes  excellent  fuel,  and  poles  when  these  are  peeled,  and  is 
highly  recommended  by  the  Forest  Service  for  planting  in  the  semi- 
arid  regions  of  our  west.  Although  it  naturally  grows  more  slowly 
under  conditions  of  adversity  it  has  great  hardiness  and  will  live 
on  almost  sterile  soils  and  produce  seed  where  almost  any  other 
tree  would  die,  although  it  cannot,  on  the  other  hand  endure 
swampy  soils.  It  is  an  excellent  shade  tree  and  is  widely  planted 
in  our  western  cities,  and  also  for  wind  breaks  in  the  prairie  states. 
Its  value  is  naturally  much  enhanced  in  those  regions  where  trees 
are  scarce. 


156  TREE    ANCESTORS 

Our  southern  hackberry,  CeUis  mississippiensis,  which  is  the 
only  other  familiar  form  here  in  America,  is  a  somewhat  smaller 
tree,  rarely  over  75  feet  in  height,  with  a  short  trunk  2  or  3  feet 
in  diameter,  spreading  branches  and  a  broad  graceful  head.  Its 
leaves  usually  have  entire  instead  of  toothed  margins,  and  the 
fruit  stones  are  pitted  instead  of  smooth  as  in  the  other  form.  The 
southern  hackberry  ranges  from  southern  Virginia  to  southern 
Illinois  and  Missouri,  and  southward  to  Florida  and  Texas. 

The  hackberry  line  is  not  certainly  known  earher  than  Eocene 
times.  It  has  been  recorded  from  the  Upper  Cretaceous  of  Europe, 
but  the  leaves  so  named  belong  in  all  probability  to  the  unfamiliar 
and  unrelated  genus  Zizyphus.  Two  forms  of  hackberry  are 
recorded  from  the  early  Eocene  of  Wyoming,  and  there  was  a  late 
Eocene  species  in  Georgia.  None  are  known  from  as  eaply  a  horizon 
as  this  in  Europe,  showing  how  imperfectly  its  geological  history 
is  known.  The  Oligocene  had  furnished  three  forms  in  France 
and  Italy  and  one  represented  by  fruits  in  the  western  United 
States.  The  Miocene  record  is  more  full,  and  comprises  traces 
of  9  different  species  widely  scattered  in  central  and  southern 
Europe,  and  present  at  that  time  in  both  Colorado  and  Wyoming. 

There  were  4  Pliocene  hackberries  in  Europe  and  Asia,  but  none 
have  as  yet  been  discovered  in  the  limited  Pliocene  plant  beds  of 
North  America.  The  Pliocene  hackberry  of  France  and  Germany 
appears  to  have  been  directly  ancestral  to  an  existing  species  found 
from  the  Caucasus  to  Upper  India,  and  a  similar  close  affinity  is 
shown  to  this  same  form  by  the  Pliocene  hackberry  found  fossil 
in  Japan.  Pliocene  species  are  also  known  from  Slavonia  and 
Indo-China. 

The  rigors  of  Pleistocene  times  apparently  killed  off  the  hack- 
berries  in  all  except  the  extreme  southeastern  part  of  Europe, 
although  a  fossil  species  of  that  age  has  been  recorded  from  Hun- 
gary. A  doubtfully  extinct  species  has  been  described  from  the 
Pleistocene  of  Maryland,  The  common  hackberry  has  been  found 
fossil  in  Virginia,  and  beautifully  preserved  and  characteristic 
stones  of  our  southern  hackberry  have  been  found  in  the  wind 
blown  Pleistocene  deposits  known  as  loess  in  Mississippi. 


CHAPTER  XV 

The  Plat  anus  or  Buttonball 

The  plane-trees,  sycamores,  and  buttonball  or  buttonwood  trees, 
comprise  the  family  Platanaceae  and  well  repay  consideration. 
Not  only  are  some  of  them  among  the  most  attractive,  but  they 
are  the  most  massive  among  our  deciduous  trees,  even  if  they  are 
not  the  tallest.  Pliny  tells  us  that  "no  tree  whatsoever  which  so 
well  defends  us  from  the  heat  of  the  sun  in  summer,"  and  Evelyn 
writes  of  it  in  the  following  language:  "the  incomparable  and  shady 
Platanus,  that  so  beautiful  and  precious  tree  which  we  read  the 
Romans  brought  out  of  the  Levant."  These  writers  referred  to 
the  Oriental  species,  and  the  earlier  botanists  Hke  Willdenow  de- 
nied that  the  plane  tree  was  indigenous  in  North  America.  Our 
plane  is  equal  in  every  respect  to  the  Old  World  tree  although  it  is 
said  to  be  less  hardy  in  artificial  plantings,  consequently  the 
Oriental  tree  is  common  in  our  city  parks.  The  two  are  scarcely 
distinguishable  but  the  native  tree  has  soHtary  buttonballs  or  fruits 
whereas  the  oriental  tree  has  several  on  a  single  stalk. 

They  are  a  widely  scattered  but  waning  type  in  these  modern 
days,  for  the  family  consists  of  the  single  genus  Platanus  with  only 
6  or  7  species  of  southwestern  Asia,  Eastern  and  western  North 
America,  Mexico  and  Central  America.  The  members  of  this 
small  group  are  very  uniform  in  general  appearance,  with  large 
deciduous  leaves,  minute  flowers  in  closely  packed  pendulous  heads 
that  remain  attached  during  the  winter,  during  which  season  the 
pappose  fruits  are  widely  distributed  by  the  winds.  The  leafstalks 
are  enlarged  at  the  base  to  enclose  the  winter  buds;  and  the  bark 
is  very  thin,  smooth,  and  pale  green  or  whitish.  The  wood  is 
likewise  rather  uniform,  in  all  being  Hght  brownish  or  reddish  in 
color  with  wide  rays.  It  splits  poorly  and  in  general  is  of  secondary 
commercial  importance. 

The  known  ancestral  history  of  these  trees  extends  back  into 
the  dim  past  a  staggering  number  of  thousands  or  even  miUions 

157 


158  TREE   ANCESTORS 

of  years.  A  still  flourishing  forest  giant  with  a  height  of  upwards 
of  170  feet  and  a  trunk  diameter  of  10  or  11  feet,  which  are  the 
dimensions  of  some  individuals  of  our  American  sycamore  {Platanus 
occidentalis  L.),  has  survived  more  changes  in  human  history  than 
almost  any  royal  or  ducal  line.  Columbus  might  have  seen  a  still 
surviving  one  as  a  young  tree  had  he  penetrated  inland  along  the 
river  bottoms  of  our  southern  states.  The  family  history  is  sur- 
passingly more  majestic  for  it  extends  back  to  the  days  when  even 
the  ape-man  was  a  distant  promise  and  the  reptilian  tribe  of 
animals  were  the  lords  of  creation.  The  gigantic  uncouth  dino- 
saurs of  the  late  Cretaceous,  so  many  of  which  have  been  unearthed 
and  are  now  mounted  in  our  larger  museums,  carry  us  a  long  way 
back  and  yet  we  know  from  the  records,  that  when  the  breath  of 
life  left  their  massive  bulks  some  of  the  leaves  that  fell  around  them 
were  those  of  plane  trees  not  very  different  from  the  leaves  that 
strew  the  ground  in  our  parks  in  October. 

These  trees  have  interests  for  the  forester,  the  lumberman,  the 
votary  of  culture  and  the  botanist.  For  the  latter  they  have  an 
especial  interest  because  of  their  affinity  with  the  figs  (another 
group  of  great  antiquity)  and  their  disputed  position  in  the  current 
schemes  of  classification. 

A  brief  consideration  of  the  Cretaceous  records  of  Platanus  sheds 
a  significant  Hght  on  the  place  of  origin  of  the  genus.  Excluding 
the  Laramie  formation,  since  its  records  are  confused  in  the  Htera- 
ture  with  those  of  the  basal  Eocene,  I  have  collected  the  following 
references  to  the  existence  of  Platanus  during  the  Cretaceous:  The 
oldest  occurrences  are  two  species  in  the  Raritan  formation  of  the 
New  Jersey  region  and  two  different  species  from  the  lower  beds 
of  the  Tuscaloosa  formation  of  the  Alabama  region.  Very  slightly 
younger  are  the  strata  of  the  Dakota  Group  extending  from  Minne- 
sota and  Colorado  to  Texas  from  v/hich  Lesquereux  has  described 
ten  species  and  varieties.  About  the  same  age  as  the  latter  is  the 
Magothy  formation  of  our  Northern  Atlantic  coastal  plain  with 
one  species  and  the  Atane  beds  of  West  Greenland  with  another. 
The  somewhat  younger  Patoot  beds  of  West  Greenland  furnish 
one  species,  there  is  artiother  in  the  Ripley  formation  of  Eastern 


THE  PLATANUS  OR  BUTTONBALL  159 

Alabama  and  a  third  in  the  Montana  Group  of  Utah.  These 
American  records  total  16  forms.  The  only  other  Cretaceous 
records  known  to  me  are  the  not  certain  identification  of  2  Dakota 
Group  forms  from  the  Upper  Cretaceous  of  Argentina,  1  cer- 
tainly not  a  Platanus,  and  3  supposed  species  from  the  Ceno- 
manian  of  Bohemia  described  by  Velenovsky  and  Marik,  The 
latter  I  regard  as  referable  to  the  probably  alHed  genus  Credneria 
of  Zenker. 

Regarding  the  authenticity  of  the  botanical  determination  of 
these  various  species  it  is  probable  that  some  of  the  records  are 
worthless,  but  enough  remain  which  are  based  upon  an  abundance 
of  absolutely  characteristic  leaves,  in  some  cases  accompanied  by 
typical  fruits,  to  render  it  certain  that  in  Middle  Cretaceous  times 
ancestral  plane  trees  were  an  abundant  element  in  the  flora  of 
North  America,  and  that  later  in  the  Cretaceous  they  had  spread 
to  South  America  and  the  Arctic  region.  They  may  have  con- 
tinued across  the  latter  region  into  Europe  although  the  records 
are  not  entirely  convincing  as  regard  the  Cretaceous  but  are  more 
ample  in  support  of  such  a  migration  in  the  Tertiary. 

These  early  ancestors  had  somewhat  elongated  rhomboidal 
leaves,  with  irregularly  and  remotely  toothed  margins,  decurrent 
on  the  petiole,  which  was  conspicuously  enlarged  at  the  base. 
There  was  a  tendency,  not  especially  pronounced,  toward  palmate 
triloba tion.  The  floral  axes  were  already  shortened  and  aggre- 
gated and  the  fruiting  heads  were  racemose  as  is  indicated  by  the 
predominancy  of  this  habit  in  the  existing  species  and  its  frequent 
occurrence  in  forms  like  Platanus  occidentalis  that  normally  have 
but  one  fruiting  head  to  a  peduncle.  These  ancestral  leaf  char- 
acters are  deduced  from  the  form  of  the  earhest  species  and  from 
the  substantial  agreement  between  them  and  the  leaves  of  modern 
seedlings  and  adventiLive  shoots  from  old  stumps  both  of  which 
are  supposed  to  exhibit  more  or  less  reversionary  characters. 
Several  of  these  are  figured  in  the  present  connection. 

Reacting  to  the  genial  influences  of  the  Cretaceous  climate  these 
early  forms  soon  broadened  their  leaves,  which  also  became 
lobate,  so  that  Platanus  Kilmmeli  Berry  of  the  Magothy  Forma- 


160  TREE   ANCESTORS 

tion  is  scarcely  distinguishable  from  the  leaves  of  the  existing 
species,  especially  Platanus  orientalis.  Its  leaves  are  exceedingly 
abundant  and  the  clays  in  places  are  packed  with  the  remains  of 
its  fruits — true  midcretaceous  "buttonballs.''  From  that  remote 
age  to  the  present  time  Platanus  leaves  have  all  shown  a  very 
strong  generic  likeness  so  that  they  are  relatively  easy  of  deter- 
mination. 

A  quarter  of  a  century  ago  Professor  Ward  wrote  a  paper  on 
the  paleontologic  history  of  the  genus  Platanus^  in  which  he  ad- 
vocated the  probable  origin  of  the  modem  stipules  from  basilar 
leaf  lobes.  This  suggestion  was  based  on  the  basal  lobes  of  several 
early  Tertiary  species  and  the  occasional  occurrence  of  comparable 
lobes  in  the  modern  Plaianus  occidentalis .  This  suggestion  while 
interesting  has  not  met  with  a  ready  acceptance.  At  the  time  that 
Ward  wrote  much  less  was  known  of  the  paleontologic  history  of 
the  genus,  especially  its  earlier  manifestations,  than  is  known  today. 
At  the  present  time  the  major  outlines  of  this  history  can  be  sketched 
in  with  a  good  deal  of  certainty. 

With  the  dawn  of  the  Eocene,  Platanus  is  abundant  in  North 
America,  its  original  home.  It  would  seem  that  the  Eocene  v/it- 
nessed  the  greatest  specific  differentiation  of  the  genus  for  no  less 
than  sixteen  different  species  have  been  desciibed.  North  America 
is  still  the  home  of  the  majority  of  these  but  the  genus  had  un- 
doubtedly spread  into  Asia  and  it  is  exceedingly  common  in  the 
Arctic  regions  in  the  so-called  Arctic  Miocene  which  is  really  much 
older  than  Miocene.  From  these  far  northern  and  now  boreal 
lands  Platanus  has  been  recorded  in  Siberia,  Greenland,  Iceland 
and  Spitzbergen.  At  this  period  it  appears  to  have  been  too  warm 
in  low  latitudes,  for  Platanus  is  absent  from  the  Eocene  iloras  of 
southeastern  North  America  where  the  remains  of  tropical  strand 
floras  are  found,  and  from  the  south  European  Eocene.  The 
abundant  American  species  occur  for  the  most  part  in  the  low 
hilly  country  which  marks  the  site  of  the  present  Rocky  Moun- 
tains.    From  some  of  these  basins,  which  at  that  time  enjoyed  a 

'  Ward.  Proc.  U.  S.  Natl.  Mus.,  11:  1888,  pp.  39-42,  pis.  17-22. 


Fig.  33.  Some  Ancestral  Forms  of  Buttonball  Leaves  (About  f 
Natural  Size) 

1,  2.  Leaves  of  adventitive  twigs  from  old  stumps  of  the  existing  Platanus 
occidentalis  Linn. 

3.  A  leaf  of  a  seedling  of  the  species. 

4.  Platanus  shirleyensis  Berry,  an  Upper  Cretaceous  Platanus  from  Alabama. 

5.  A  non-lobate  leaf  of  Platanus  Kummeli  Berry  from  the  Upper  Cretaceous 
of  New  Jersey. 

161 


162  TREE    ANCESTORS 

humid  climate  and  supported  a  rich  fauna  and  flora,  plane-tree 
leaves  nearly  two  feet  in  diameter  have  been  collected.  The  most 
southern  Eocene  record  in  the  European  area  thus  far  discovered 
is  in  deposits  interbedded  with  the  basaltic  lava  flows  of  this  period 
on  the  Isle  of  Mull  from  which  staminate  catkins,  fruit  and  leaves 
have  been  described  as  Platanus  hehridicus. 

The  Oligocene  period  which  succeeds  the  Eocene  was  a  period 
of  land  emergence  and  dry  hot  climates.  Consequently  the  locali- 
ties where  plane  trees  may  be  presumed  to  have  flourished  have 
been  regions  where  their  .  remains  failed  to  become  preserved. 
North  America  is  especially  poor  in  Oligocene  plant  remains  of  all 
kinds  and  no  Oligocene  species  of  Platanus  have  been  discovered 
although  they  must  have  been  abundant  since  they  again  appear 
in  the  North  American  fossil  record  after  the  close  of  the  Oligocene. 
Two  or  three  species  of  Platanus  of  Oligocene  age  have,  however, 
been  discovered  in  European  plant  beds. 

The  Oligocene  period  was  followed  by  the  Miocene,  a  period 
during  the  early  part  of  which  the  Oligocene  elevation  culminated 
and  subsidence  set  in.  Tliis  was  accompanied  by  a  striking  cli- 
matic change,  at  least  in  the  eastern  United  States.  In  our 
Southern  States  the  Oligocene  faunas  and  floras  were  such  as 
flourish  today  under  the  equator.  The  succeeding  Miocene  de- 
posits which  overlie  them  in  northern  Florida  and  elsewhere  con- 
tain leaves  of  trees  of  the  temperate  zone  and  the  remains  of  a 
marine  fauna  which  had  advanced  from  the  New  Jersey-Maryland 
region  as  the  tropical  fauna  was  driven  southward.  North  America 
does  not  contain  very  many  Miocene  plant  beds  but  nevertheless 
the  remains  of  plane  trees  have  been  collected  from  Oregon  and 
CaHfomia  on  the  Pacific  coast,  from  the  Yellowstone  Park,  and 
from  Virginia  on  the  Atlantic  Coast.  In  Europe  where  Miocene 
plant  beds  are  more  frequent  the  leaves  of  Platanus  are  abundant 
and  widely  distributed  although  they  belong  to  but  few  species — 
five  have  been  described.  One  of  these,  Platanus  aceroides,  first 
described  by  Goeppert  in  1852,  is  the  dominant  Miocene  form  of 
the  whole  Northern  Hemisphere.  Its  European  records  include 
Baden,  Switzerland,  Silesia,  Italy  and  many  localities  in  Austria 


THE  PLATANUS  OR  BUTTONBALL  163 

Hungary — a  region  remarkably  rich  in  plant  bearing  deposits  of 
Tertiary  age. 

Succeeding  the  Miocene  are  the  deposits  of  the  Pliocene  lakes, 
rivers  and  seas.  The  Phocene  is  the  youngest  period  of  the 
Tertiary  age.  North  America  was  of  much  the  same  geographical 
extent  as  it  is  today  and  fossil  plants  are  almost  entirely  unknown ; 
consequently,  although  the  plane  trees  were  unquestionably  present 
they  have  left  no  records.  Europe  on  the  other  hand  was  a  region 
of  great  geographical  change  and  mountain-making.  The  chief 
of  these  changes  centered  about  the  Mediterranean  Sea,  the  center 
of  the  classical  world.  At  one  time  its  waters  withdrew  westward 
to  Italy  leaving  behind  a  chain  of  lakes.  A  wide  grassy  plain 
occupied  the  present  Aegean  region,  another  broad  land  bridge 
stretched  across  from  Sicily  to  the  site  where  Carthage  was  subse- 
quently founded  on  the  African  coast,  and  a  third  united  Spain 
with  Morocco.  At  another  time  the  Mediterranean  waters  ex- 
tended over  a  vast  area  in  southeastern  Europe.  The  climate 
was  mild  and  humid  and  some  of  the  finest  forests  that  Europe 
has  ever  known  clothed  its  shores.  Pliocene  remains  of  Platanus 
have  been  collected  in  Italy  along  the  foothills  of  the  rising  Apen- 
nines, from  France,  Spain,  Styria,  and  Slavonia. 

-The  Tertiary  was  succeeded  by  the  Quaternary,  the  fourth  age 
of  the  older  cosmogonists  who  divided  the  rocks  into  primary, 
secondary,  tertiary  and  quaternary.  The  latter  includes  the 
Pleistocene,  and  the  Recent  period  in  which  we  are  now  living. 
The  Pleistocene  is  marked  by  chmatic  changes  which  brought 
about  the  extensive  glaciation  of  the  ice  age,  that  most  profound 
factor  in  the  distribution  of  modem  animals  and  plants.  The 
most  interesting  Pleistocene  deposits  in  the  eyes  of  the  botanist 
are  those  of  old  forest  beds  and  peat  bogs.  These  show  that  the 
plane  tree  was  still  present  in  central  Europe,  although  today  it 
is  not  a  native  in  that  region  except  as  it  is  planted.  American 
records  show  that  our  modem  sycamore  was  already  in  existence 
with  habits  much  like  it  has  at  the  present  time.  Its  leaves  and 
fruits  have  been  unearthed  in  the  clays  of  river  terraces  around 
Morgantown,  West  Virginia;  in  the  sediments  that  tilled  the  bone 


164  TREE   ANCESTORS 

cave  at  Port  Kennedy,  Pennsylvania,  once  the  lair  of  various 
Pleistocene  void  animals;  and  in  the  buried  river  swamps  of  North 
Carohna  and  Alabama.  During  an  Interglacial  period  it  spread 
northward  to  southern  Canada  and  left  its  leaves  in  the  clays  of 
the  Don  Valley  near  Toronto. 

I  have  written  several  similar  brief  sketches  of  the  geologic 
history  of  different  American  forest  trees  and  hope  to  add  similar 
accounts  of  others  from  time  to  time.  My  object  is  not  purely 
cultural.  I  hope  that  my  readers  will  become  awake  to  the  records 
of  the  ages  preserved  in  the  structure  and  habits  of  our  commoner 
forest  trees.  This  fruiting  habit  acquired  perhaps  in  the  Eocene 
three  milHons  of  years  ago,  this  anatomical  feature  of  the  wood 
acquired  perhaps  in  the  Upper  Cretaceous — the  changing  environ- 
ment of  the  successive  ages  that  moulded  each  type  until  it  is 
what  we  see  it  today.  Let  imagination  play  over  the  world  his- 
tory enacted  in  the  shadows  of  these  trees — the  building  of  the 
Rockies,  the  evolution  of  the  mammals  and  of  primitive  man. 
If  the  building  of  the  tower  of  Babel,  the  hanging  gardens  of  Baby- 
lon, or  the  pyramids,  are  awe-inspiring,  what  shall  we  say  of  the 
slow  formation  of  the  Himalayas,  during  which  faunas  came  and 
went  while  the  sycamore  line  flourished  on  and  on.  Beside  the 
sycamore,  oak  or  pine,  the  Rosetti  stone  or  Elgin  marbles  are 
things  of  yesterday.  Why  should  we  not  venerate  our  forest  trees 
as  we  do  man-built  temples  of  classic  days?  When  we  are  con- 
fronted by  a  sycamore  that  witnessed  De  Soto  crossing  the  Tom- 
bigbee  shall  we  not  hesitate  at  the  wanton  destruction  of  what 
should  mean  so  much  to  us? 


CHAPTER  XVI 

The  Magnolia  and  Tulip-Tree 

Both  of  these  famihar  trees  belong  to  the  magnolia  family,  and 
although  we  are  not  here  concerned  with  the  other  members  of 
this  family  they  exhibit  much  that  is  of  interest  to  the  student  of 
geographical  distribution  and  I  do  not  think  that  any  family  of 
trees  better  illustrates  the  main  outlines  of  the  general  history  of 
a  large  number  of  tree  types. 

The  magnolia  family  at  the  present  time  contains  2  genera 
which  are  confined  to  the  southeastern  Asiatic  region  (Kadsura, 
Michelia),  and  one  that  is  limited  to  the  island  of  New  Caledonia 
(Zygogynum).  The  other  5  genera  which  round  out  the  family, 
namely:  Magnolia,  Liriodendron,  Schizandra,  Illicium,  and  Drimys, 
are  each  divided  between  the  Orient  and  the  Occident.  All  of 
these  except  Liriodendron  have  more  than  a  single  species  in  both 
regions.  Magnolia  and  Liriodendron  are  the  most  northern, 
Schizandra  and  Illicium  are  more  southerly  and  overlap  part  of 
the  range  of  the  preceding  two  genera,  Taulauma  is  tropical,  and 
Drimys  goes  farthest  southward  in  both  hemispheres  and  does 
not  reach  the  North  Temperate  Zone  at  all,  extending  southward 
to  Australia  and  New  Zealand  in  the  Orient,  and  to  southern  Chile 
in  the  Occident,  and  showing  moreover  a  most  primitive  type  ot 
wood  that  is  entirely  without  the  larger  ducts  or  pores  that  are  so 
characteristic  of  all  but  a  very  few  of  the  higher  plants. 

No  family  is  more  obviously  of  northern  origin,  none  is  better 
represented  in  the  forests  floras  of  Upper  Cretaceous  times  through- 
out the  northern  lands,  or  better  exhibits  the  southward  extension 
so  characteristic  of  many  other  types  as  the  pressure  of  plant 
populations  behind  them  and  the  availability  of  suitable  land 
routes  to  the  southward  permitted.  Drimys,  the  most  primitive 
in  its  anatomy,  is  today  found  farthest  from  its  original  home. 
Unfortunately  the  geological  history  of  this  genus  is  practically 

165 


Fig.  34.  Sketch  Map  Sho\ving  the  Fossil  Occurrences  of  the  Magnolia 


Fig.  35.  Sketch  Map  Showing  the  Distribution  of  the  Different  Genera 

OF  THE  Magnolia  Family 

166 


THE   MAGNOLIA  AND   TULIP-TREE  167 

unknown  but  the  fact  that  the  species  are  distinct  in  each  region, 
i.e.,  in  AustraHa,  New  Caledonia,  New  Zealand  and  America, 
indicates  that  they  were  very  ancient  immigrants  into  those  regions 
before  the  present  geography  had  come  into  existence. 

These  items  regarding  the  family  seem  to  me  to  be  of  sufficient 
general  interest  to  warrant  mentioning  them  in  an  introduction 
to  the  two  types  in  the  family  that  are  the  subject  of  this  chapter, 
and  I  have  shown  the  modern  distribution  of  the  family,  as  out- 
Kned  above,  on  the  accompanying  sketch  map  (figure  35). 

THE   MAGNOLIA 

I  expect  that  to  most  of  us  magnolia  means  the  large  pinkish 
flowered  exotics  of  our  lawns  and  parks  which  have  been  so  gen- 
erally planted  in  recent  years;  or  perhaps  the  word  suggests  the 
fragrant  yellowish  white  blossoms  of  the  swamp  magnoha  of  our 
eastern  States  which  are  sometimes  peddled  by  street  vendors  in 
the  cities  of  our  Atlantic  seaboard.  It  we  come  from  the  rural 
south,  or  have  visited  some  of  the  old  towns,  such  as  Augusta, 
Georgia,  we  will  be  acquainted  with  the  tall  tree  with  shiny  ever- 
green leaves  which  is  just  "magnolia"  and  without  which  the 
door  yard  of  any  southern  mansion  was  incomplete.  This  last  is 
a  large  and  handsome  tree,  and  was  formerly  frequently  planted 
in  the  yards  of  the  older  and  more  pretentious  houses  as  far  north- 
ward as  Baltimore  and  Philadelphia. 

There  are  about  a  score  of  existing  magnolias,  the  name  itself 
being  in  honor  of  Pierre  Magnol,  professor  of  botany  at  Montpellier, 
who  died  in  1715,  Of  these  about  one-third  are  natives  in  south- 
eastern North  America,  and  the  balance  occur  from  the  Himalayas 
eastward  in  southeastern  Asia.  Several  of  these  Asiatic  forms 
put  forth  their  large  blossoms  before  they  unfold  their  leaves,  and 
it  is  these  that  are  much  used  for  ornamental  plantings  throughout 
the  Temperate  Zone. 

All  of  the  magnolias  have  rather  large  showy  blossoms,  and  the 
leaves  vary  a  great  deal  from  species  to  species  in  both  their  form 
and  consistency.  Our  large  leaved  cucumber-tree,  Magnolia 
macro phylla,  has  the  distinction  of  having  the  largest  entire  leaves 


168  TREE    ANCESTORS 

of  any  of  our  trees.  They  are  light  green  in  color  and  oblong  in 
form  and  are  often  30  inches  long  and  9  or  10  inches  wide.  This 
tree  is  not  common  and  occurs  as  scattered  individuals,  haunting 
moist  ravines  where  the  soil  is  deep  and  rich,  in  the  region  between 
North  Carolina  and  Alabama.  Our  umbrella-tree  or  elkwood. 
Magnolia  tripctala,  an  Appalachian  species  found  scattered  from 
Pennsylvania  to  Alabama,  also  has  large  leaves,  sometimes  20 
inches  long  and  10  inches  wide.  Both  of  these  and  others  of  our 
native  species,,  have  frequently  been  cultivated  as  ornamental  trees, 
both  in  this  country  and  Europe,  and  are  hardy  as  far  northward 
as  the  southern  New  England  coastal  region. 

The  only  one  of  our  native  species  whose  natural  range  extends 
that  far  northward  is  the  sweet  bay  or  swamp  magnolia,  a  bush 
or  slender  tree  of  deep  swamps,  which  post  glacial  climatic  changes 
have  left  stranded  in  Essex  County,  Massachusetts,  and  on  Long 
Island,  and  which  ranges  southward  to  peninsular  Florida  and 
eastern  Texas. 

The  magnolias  contribute  to  the  higher  things  of  Hfe  rather  than 
to  the  utiHties,  and  invariably  suggest  wayfarers  from  the  orient 
rather  than  the  staid  natives  of  the  Temperate  Zone.  Not  all  of 
them  have  blossoms  that  are  especially  beautiful  and  they  turn 
to  a  yellowish  brown  rather  rapidly  when  picked,  and  nothing  is 
more  dismal  than  one  of  the  Asiatic  forms  that  has  been  touched  by 
a  late  spring  frost,  but  when  favored  by  the  weather  nothing  in 
these  chmes  is  more  gorgeous.  Some  of  the  flowers  are  of  sufficient 
consistency  that  in  exceptional  cases  they  have  been  covered  by 
sediments  before  they  decayed  and  thus  preserved  as  fossils,  and 
several  instances  of  this  sort  have  been  recorded.  The  peculiar 
cone-hke  fruits  have  also,  and  more  frequently  been  preserved  as 
fossils. 

The  fossil  record  of  the  magnohas  is  a  long  and  extensive  one  and 
worthy  of  a  more  complete  exposition  than  I  can  give  it  here. 
From  the  sediments  laid  down  in  the  far  off  days  of  the  Upper 
Cretaceous  the  leaves  of  no  less  than  23  species  of  magnoha  have 
been  described,  and  although  some  of  these  determinations  may 
be  legitimately  questioned,  others  seem  to  be  authentic.     Several 


THE    MAGNOLIA   AND    TULIP-TREE  169 

of  these  early  magnolias  were  widely  distribuled,  especially  a 
group  of  forms  found  in  western  Greenland  which  ranged  south- 
ward in  what  is  now  the  Atlantic  Coastal  Plain  from  Marthas 
Vineyard  to  Texas. 

A  second  Upper  Cretaceous  display  of,  in  part  identical  forms, 
of  magnolias  is  now  found  in  the  Dakota  sandstone  of  Kansas  and 
Nebraska — the  Dakota  sandstone  representing  the  shoreward 
sands  spread  over  the  western  interior  of  North  America  by  the 
advancing  sea  of  the  Upper  Cretaceous,  which  swept  northward 
at  that  time  from  the  Gulf  of  Mexico  almost  or  quite  to  the  Arctic 
Ocean.  A  Cretaceous  magnolia  has  been  recorded  from  western 
Canada,  a  second  from  Vancouver  Island,  and  a  later  Cretaceous 
form  has  been  found  in  Wyoming  and  Tennessee.  In  the  Old 
World  there  was  an  early  Upper  Cretaceous  species  in  Portugal, 
and  three  additional  and  sHghtly  later  forms  have  been  found  in 
Bohemia  and  Moravia. 

The  Eocene  magnoHas  number  about  a  score  of  species,  all  differ- 
ent from  their  Upper  Cretaceous  ancestors,  and  thus  hinting  at 
the  long  time  interval  that  we  know  intervened  between  the  marine 
deposits  of  these  two  geological  periods,  when  the  present  land 
areas  of  the  globe  were  elevated  and  the  seas  were  restricted  which 
fact  led  the  early  geologists  to  draw  the  boundary  between  the 
Mesozoic  and  the  Cenozoic  at  this  horizon.  The  Eocene  magnolias 
have  an  equally  wide  distribution  as  those  of  the  Cretaceous. 
They  occur  in  both  the  basal  or  Paleocene,  and  in  the  upper  Eocene 
of  North  America  and  Europe — the  far  northern  records  of  their 
former  existence,  to  be  enumerated  presently,  belonging  in  the 
second  category.  These  Eocene  records  include  Greenland,  Spitz- 
bergen,  Alaska,  Sachalin  Island  and  western  Canada  on  the  north 
and  Oregon,  Cahfornia,  Wyoming,  Colorado,  New  Mexico,  Missis- 
sippi, Tennessee,  Louisiana,  France,  Germany,  Bohemia  and  Croatia 
on  the  souch.  Beside  the  remains  of  leaves  both  flower  parts  and 
characteristic  fruits  have  been  found  in  the  rocks  of  this  age. 

During  Ohgocene  times  which  succeeded  those  of  the  Eocene,  8 
differ-ent  magnohas,  all  from  the  Old  World,  have  been  described. 
They  were  apparently  most  abundant  during  that  time  in  Italy, 


170  TREE   ANCESTORS 

but  occurred  also  in  France  and  Russia.  As  I  have  had  occasion 
to  state  so  many  times  in  these  sketches  of  tree  ancestors  our 
American  plant  records  are  especially  deficient  for  the  Oligocene 
and  Pliocene  so  that  the  fact  that  I  am  unable  to  enumerate  any 
Ohgocene  magnoUas  from  North  America  does  not  mean  that 
none  existed  for  we  are  quite  sure  that  they  did,  it  simply  means 
that  the  book  of  history  whose  pages  are  the  rocks  has  the  Ohgo- 
cene chapter  torn  out  of  the  American  record. 

Sixteen  Miocene  species  of  Magnolia  have  been  recorded.  These 
records  include  both  Europe  and  North  America,  and  the  magnolias 
were  about  as  abundant  then  as  now  although  their  range  had  not 
yet  become  as  restricted  as  it  is  today.  Miocene  Asia  probably 
had  its  magnolias  as  in  modern  times,  but  whereas  magnohas 
were  abundant  in  Miocene  Europe  none  of  these  survived  the 
Pleistocene  glaciation. 

The  closing  days  of  the  Tertiary  period,  or  Pliocene  times,  have 
furnished  11  magnolias,  found  in  North  America,  Europe,  and 
eastern  Asia  (Japan) .  In  North  America  these  Pliocene  magnolias 
occurred  in  what  is  now  the  Atlantic  Coastal  Plain — the  Pacific 
coastal  region  and  western  interior  regions  being  at  that  time 
much  as  they  are  in  modem  times,  both  geographically  and  climati- 
cally. In  Europe  most  of  the  PHocene  records  are  from  countries 
bordering  the  Mediterranean,  that  is,  Spain,  France,  and  Italy, 
but  magnolias  were  still  present  in  the  late  PHocene  in  both  Holland 
and  Germany.  These  last  were  apparently  exterminated  by  the 
Pleistocene  glaciation,  thus  leaving  Europe  without  any  native 
magnolias  in  the  modern  period.  Two  forms  of  Magnolia  were 
described  many  years  ago  from  the  Tertiary  of  Australia,  but 
these  are  not  regarded  as  authentic  representatives,  and  have  been 
entirely  ignored  in  {he  present  discussion. 

Pleistocene  magnolias  are  restricted  to  the  remains  of  the  exist- 
ing sweet  bay,  Magnolia  virginiana,  found  in  deposits  of  that  age 
in  southern  Florida.  The  accompanying  sketch  map  shows  the 
localities  from  which  fossil  magnohas  have  been  described  and 
shows  how  much  more  extensive  was  their  range  in  the  past  as 
compared  with  what  it  is  today. 


THE   MAGNOLIA   AND    TULIP-TREE  171 


THE  TULIP-TREE 


The  tulip-tree  is  one  of  the  largest  and  the  most  valuable  of  our 
eastern  trees,  a  favorite  in  private  parks,  and  increasingly  planted 
in  suburbs  throughout  the  eastern  states  and  in  central  and  western 
Europe.  It  is  otherwise  unknown  in  the  latter  continent,  although 
it  was  not  at  all  uncommon  there  for  thousands  of  years  previous 
to  the  Ice  Age  and  before  the  advent  of  man  in  that  region. 

Until  recently  our  common  tulip-tree,  or  yellow  poplar  as  it  is 
often  called,  especially  by  lumbermen,  although  it  is  entirely  un- 
related to  the  true  poplars,  was  thought  to  be  the  sole  living  repre- 
sentative of  the  genus  Liriodendron — the  name  is  from  the  Greek 
and  signifies  the  tree  with  Hly-like  flowers,  a  singularly  appropriate 
etymology.  A  few  years  ago  a  very  similar  tree  was  discovered 
in  China,  whose  flora  shares  so  much  with  that  of  eastern  North 
America.  It  is  so  like  its  American  relative  that  there  was  some 
question  whether  or  not  it  really  differed  at  all.  Technically  it 
was  christened  as  the  Chinese  variety  of  the  American  tree,  but 
subsequently  it  has  quite  generally  been  given  species  rank,  so 
that  these  two — Liriodendron  chinensis  in  the  Orient  and  Lirioden- 
dron tulipifera  in  the  Occident,  on  the  opposite  sides  of  the  Northern 
Hemisphere,  represent  the  last  survivors  of  an  ancient  race.  They 
hold  their  titles  in  fee  simple  from  the  Upper  Cretaceous,  but  now 
much  reduced  in  their  territories  as  compared  with  their  far  flung 
range  in  the  past  over  North  America,  Asia,  Europe  and  the  Arc- 
tic. Time  was  once  when  the  sun  never  set  on  the  tuhp-tree,  but 
the  old  days  will  never  come  back  for  our  trees — humanity  has 
largely  replaced  them. 

Our  American  tulip-tree,  Liriodendron  tulipifera,  has  a  tall 
straight  columnar  trunk  with  deeply  furrowed  bark,  and  relatively 
small  branches  which  are  not  thrown  out  nearer  than  80  to  100 
feet  of  the  ground.  The  tree  frequently  reaches  a  height  of  200 
feet  and  a  trunk  diameter  of  from  8  to  12  feet.  It  reaches  its 
largest  size  in  the  deep  rich  soil  of  the  lower  Ohio  valley.  There  is 
an  immense  old  tuHp-tree  at  Annapolis  named  for  General  Lafayette, 
and  one  old  colonial  manor  in  southern  Maryland  has  a  long  en- 
trance drive  bordered  wdth  old  giants  of  this  species. 


172 


TREE   ANCESTORS 


The  tulip-tree  is  extensively  lumbered,  not  only  because  of  its 
size  and  the  extent  of  clear  wood  that  it  yields,  but  because,  al- 
though not  strong,  the  wood  is  soft  and  easily  worked,  and  there 
is  a  very  large  demand  for  it  for  interior  finish,  boat  building, 
shingles,  woodenware,  etc. 

It  and  its  relative,  the  magnolia,  are  practically  our  only  forest 
trees  with  large  flowers,  those  of  the  tuHp-tree  being  cup-shaped, 


Fig.  36.  Sketch  Map  Showing  Existing  Range  (irregular  black  areas) 
AND  Fossil  Occurrences  (solid  circles)  of  the  Tulip-tree 


about  2  inches  in  length  and  breadth,  slightly  fragrant,  with  3 
large  petaloid  sepals  and  6  orange  yellow  petals  marked  with  green. 
Inside  are  the  numerous  large  stamens  and  a  central  mass  of  pistils 
which  mature  to  form  a  dry  cone-like  fruit  about  3  inches  long,  and 
made  up  of  spirally  arranged,  overlapping,  stiffly  winged  fruits, 
which  the  winters  winds  gradually  detach  and  whirl  against  our 
window  panes. 


THE    MAGNOLIA  AND    TULIP-TKEE  173 

The  flowers  do  not  appear  until  after  the  leaves  are  out  in  the 
spring,  and  as  the  trees  are  tall  they  are  not  as  familiar  as  they 
deserve  to  be.  Some  people  never  see  them  for  they  are  hard  to 
come  at,  are  short  stalked,  and  rather  perishable  even  when  it  is 
possible  to  pick  them.  The  tulip-tree  leaves  are  dark  green  and 
unique  in  form  and  very  handsome.  Normally  they  are  some- 
what fiddle-shaped,  like  7  of  figure  37  or  10  of  figure  38,  notched 
at  the  tip  with  two  or  three  sinuous  pointed  lobes  on  each  side. 
They  are  long  stalked  and  at  the  base  of  the  stalk  there  are  a  pair 
of  large  hghter  green  oval  leaflets  of  the  sort  that  botanists  call 
stipules.  These  serve  as  bud  scales  and  protect  the  tiny  leaflets 
during  the  winter.  The  peculiar  arrangement  of  the  leaves  in 
these  laterally  compressed  buds,  where  they  are  recurved  or  bent 
down  so  that  their  forked  tip  lies  at  the  base  of  the  future  stalk, 
is  the  reason  why  they  have  the  notched  tip  so  unHke  the  majority 
of  leaves. 

The  tulip-trees  are  undoubtedly  derived  from  distant  ancestors 
with  pointed  lanceolate  leaves  Hke  those  of  the  magnolias,  and  we 
as  yet  have  no  clue  to  the  manner  in  which  they  came  to  adopt  this 
peculiar  arrangement  of  being  tucked  away  in  the  buds  flexed 
and  folded  one  within  the  other  and  facing  first  one  side  and  then 
the  other,  for  the  leaves  are  alternate  in  their  arrangement.  Most 
tree  buds,  either  of  leaf  or  flower,  have  a  number  of  bud  scales  for 
their  protection  and  these  are  generally  resinous  (the  source  of 
^  pooG  wftx)  or  furry,  and  often  of  large  size  as  in  the  walnuts  and 
horse-chestnuts.  To  a  certain  extent  in  the  magnolias  and  es- 
pecially in  the  tulip-tree  this  function  of  protection  is  assumed 
by  the  basal  leaflets  or  stipules.  Theoretically  we  believe  that 
all  bud  scales  are  modified  leaves  or  leaf  segments,  but  in  nearly 
all  trees  the  bud  scales  have  been  so  modified  or  specialized  that 
their  history  can  not  be  readily  deciphered,  as  it  can  in  this  family, 

A  good  many  years  ago  I  spent  much  time  collecting  the  leaves 
of  the  tulip-tree  for  purposes  of  comparison  with  the  fossil  forms, 
and  the  subject  is  such  an  interesting  one  that  I  have  devoted  a 
plate  to  some  of  the  curious  shaped  leaves  of  our  recent  species 
that  illustrate  the  origin  of  the  stipules  and  that  show  how  the 


174  TREE   ANCESTORS 

life  history  of  a  modem  form  lends  to  repeat  the  Hfe  history  of  its 
ancestral  line.  Starting  wdth  figure  9  the  reader  will  note  an 
incipient  lobe  on  either  side  of  the  base  of  an  otherwise  normally 
shaped  leaf.  The  larger  of  these  two  basal  lobes,  that  on  the  right, 
has  a  peculiar  arrangement  of  the  veins  very  similar  to  the  arrange- 
ment found  in  a  modern  stipule.  The  next  stage  may  be  illus- 
trated by  figure  4  in  which  these  basal  lobes  have  become 
separate  leaflets,  like  stipules  but  at  the  top  instead  of  at  the  base 
of  the  leaf-stalk.  Or  this  second  stage  may  be  illustrated  by 
figure  3  where  the  leaf-stalk  has  not  yet  become  elongated  and 
where  on  one  side  it  is  winged,  much  like  the  condition  preserved 
in  the  Upper  Cretaceous  form  known  as  Liriodendron  alatum  (sho^\^l 
in  figure  4  on  the  plate  of  fossil  leaves)  and  on  the  other  side  the 
wing  is  separating  from  the  rest  of  the  blade  in  the  direction  of  an 
affair  that  looks  like  a  modem  stipule.  By  the  elongation  of  the 
leaf-stalk  of  a  form  like  that  shown  in  figure  3,  a  form  like  figure  1 
would  be  approximated,  figure  2  shows  a  succeeding  stage,  and  it 
needs  but  to  separate  the  stipules  from  the  leaf-stalk  of  a  form 
like  that  shown  in  figure  2  to  get  the  normal  condition  of  the  mod- 
em leaves  such  as  is  sho\^^l  in  figure  7. 

That  the  bud  scales  of  the  large  blossoms  have  a  similar  origin 
is  shown  by  the  frequent  presence  of  a  midrib  or  of  a  vestigial 
base  of  a  leaf-stalk  between  the  scales  and  this  is  frequently  elon- 
gated as  in  figure  8  with  an  awn-like  thickened  tip.  About  as 
frequently  this  elongation  will  expand  into  a  tiny  ovate  leaf  Hke 
that  shown  in  figure  6,  and  not  rarely  a  larger  and  more  normal 
shaped  leaf  like  that  shown  in  figure  5  will  be  present.  These  may 
be  compared  with  the  figures  of  the  corresponding  occurrences  in 
magnolia.  Much  the  same  sort  of  a  history  can  be  observed  in  the 
buttonball  (Platanus),  and  it  would  seem  that  these  extraordinary 
specimens  of  tulip-tree  leaves  illustrate  the  manner  of  origin  of 
the  stipules  during  Upper  Cretaceous  times. 

The  geological  record  of  the  tulip-tree  is  remarkable  in  several 
ways,  especially  in  the  great  variety  and  wide  range  of  the  Upper 
Cretaceous  forms.  The  oldest  known  are  those  of  the  Atlantic 
border  in  New  Jersey.     This  in  itself  is  interesting  because  much 


THE   MAGNOLIA   AND   TULIP-TREE 


175 


Fig.  37.  Some  Singular  Atavistic  Leaves  of  the   Existing  Tulip-tree 

(About  |  Natural  Size) 


176  TREE    ANCESTORS 

of  North  America  and  the  Arctic  archipelago  to  the  northward  had 
been  a  land  area  for  many  millions  of  years  pre\dous  to  their  mar- 
ginal flooding  by  the  Upper  Cretaceous  sea.  This  fact  is  more 
significant  than  it  may  seem  at  first  sight.  The  latest  marine 
submergence  of  the  Appalachian  province,  using  that  term  in  a 
very  broad  way  had  been  the  dwindling  sea  of  the  Carboniferous. 
This  area  and  that  lying  north  of  it  to  the  pole  itself  was  a  land 
area  during  all  of  Permian,  Triassic,  Jurassic  and  Lower  Cretaceous 
times.  When  this  land  first  emerged  from  the  Carboniferous  sea 
it  was  clothed  with  a  strange  vegetation  made  up  of  entirely  extinct 
types,  such  as  the  seed-ferns,  Calamites,  lepidodendrons  and  sigil- 
larias.  During  the  interval  between  the  Carboniferous  and  the 
Upper  Cretaceous  the  foregoing  types  had  become  entirely  extinct 
and  the  flowering  plants  had  been  evolved  and  had  rapidly  spread 
toward  that  dominance  in  the  plant  world  which  they  occupy  at 
the  present  time,  which  position  they  had  reached  as  eariy  as 
Eocene  time.  This  holds  a  still  greater  interest  for  the  human  race, 
since  practically  all  plant  foods  utihzed  by  man,  and  the  plant 
foods  utihzed  by  the  animals  upon  which  man  depends  for  meat 
(except  fishes)  are  derived  from  the  flowering  plants,  and  it  is  no 
exaggeration  to  say  that  fixed  abodes  and  agriculture  which  were 
the  basis  of  civiHzation  itself  were  conditioned  upon  the  evolution 

Fig.  38.  Fossil  Leaves  or  the  Tulip-tree  (About  §  Natur.\l  Size) 

L  Liriodcndron  meeki  Heer  from  the  Upper  Cretaceous  of  Alabama. 

2.  Liriodendron  quercijolium  Newberry  from  the  Upper  Cretaceous  of  New 
Jersey  (Raritan  formation). 

3.  Liriodcndron  viorganensis  Berry  from  the  Upper  Cretaceous  of  New  Jersey 
(Magothy  formation). 

4.  Liriodendron  alatum  Newberry  from  the  Upper  Cretaceous  of  Colorado 
(Vermejo  formation). 

5.  Liriodendron  acuminatum  Lesquereux  from   the  Dakota  sandstone  of 
Kansas. 

6.  Liriodendron  procaccinii  Unger  from  the  Tliocene  of  France. 

7.  The  same  from  the  Phocene  of  Italy. 

8.  Liriodendron  islandicum  Saporta  &  Marion  from  the  Eocene  of  Iceland. 

9.  Liriodendron  gardncri  Saporta  from  the  Eocene  of  England. 

10.  Liriodcndron  tulipifcra  Linnaeus  from  the  Pleistocene  of  North  Carolina. 


THE    MAGNOLIA    AND    TULIP-TREE 


177 


178  TREE    ANCESTORS 

of  the  flowering  plants.  It  was  then  this  evolution  during  the  Meso- 
zoic  that  made  possible  the  evolution  of  the  mammals  during  the 
Tertiary,  so  this  far  off  happening  of  Mesozoic  time  might  well  be 
considered  as  the  primary  stimulus  to  that  chain  of  events  that 
resulted  in  humanity  and  humanity's  civilization. 

The  remains  of  tulip-trees  were  also  a  prominent  element  in  the 
forests  that  clothed  the  shores  of  the  Upper  Cretaceous  sea  that 
about  the  same  time  spread  northward  from  the  Gulf  of  Mexico 
up  the  Mississippi  Valley  and  over  the  present  prairie  States.  In 
the  shore  sands  of  this  advancing  sea,  which  geologists  call  the 
Dakota  sandstone,  a  variety  of  tulip-tree  leaves  were  preserved. 
Some  students  have  argued  that  since  the  leaves  of  the  modem 
tree  are  variable  this  variety  of  Cretaceous  leaves  may  represent 
a  single  variable  species,  but  this  is  not  beheved  to  have  been  the 
case. 

There  are  at  least  9  different  kinds  of  tulip-tree  leaves  in  the 
Dakota  sandstone  ranging  in  appearance  from  the  small  Lirioden- 
dron  meekii  (fig.  1)  to  the  enormous  obtusely-lobed  Liriodendron 
giganteum  with  leaves  7  inches  in  diameter,  and  the  greatly  pointed- 
lobed  Liriodendron  quercifoliimi  (fig.  2).  Some  of  these  forms  have 
been  found  from  Texas  to  Iowa,  Kansas  and  Nebraska,  and  7 
of  them  are  confined  to  the  Dakota  sandstone.  A  similar  display 
has  been  found  in  the  Upper  Cretaceous  deposits  of  the  Atlantic 
Coastal  Plain  from  Long  Island  to  Alabama  and  Arkansas.  There 
is  1  recorded  from  Long  Island,  3  from  New  Jersey,  2  from  North 
Carolina,  1  from  Alabama,  and  2  from  Arkansas.  One  of  these 
known  as  Liriodendron  meekii  is  found  in  western  Greenland,  Ne- 
braska, in  Saxony,  and  it  has  even  been  recorded  from  Argentina, 
although  this  last  record  is  not  properly  authenticated. 

At  the  time  that  these  tuhp-trees  were  flourishing  in  Greenland, 
southeastern  North  America  and  in  the  western  interior,  other 
forms  were  present  on  our  Pacific  coast,  two  different  forms  having 
been  discovered  in  the  Upper  Cretaceous  rocks  of  Vancouver  Island. 
Somewhat  later  in  Cretaceous  time  a  second  species  occurred  in 
Saxony,  and  toward  the  close  of  the  Cretaceous  two  additional 
American  species  appear  in  the  record — one  in  western  Tennessee 


THE   MAGNOLIA   AND    TULIP-TREE  179 

and  Wyoming,  and  the  second  the  remarkable  Liriodendron  alatiim 
(fig.  4)  with  its  winged  leaf-stalks,  which  is  found  in  Colorado  and 
Utah. 

Cretaceous  times  were  brought  to  a  close  by  widespread  land 
emergence  and  this  emergent  condition  prevailed  for  a  very  long 
period  of  time,  in  fact  at  no  subsequent  stage  of  the  earth's  history 
was  there  anything  approaching  the  degree  of  submergence  attained 
during  the  Cretaceous.  Finally  there  was  a  period  of  renewed 
submergence  which  ushered  in  the  Tertiary.  This  early  Tertiary 
renewal  of  sea  expansion  resulted  in  such  a  disposition  of  the  land 
and  water  that  extensive  mediterranean  seas  had  free  connections 
with  the  Arctic  not  only  from  the  Atlantic  and  Pacific  oceans,  but 
also  across  Asia,  and  this  resulted  in  mild  and  comparatively  uni- 
form chmates.  The  fossil  floras  of  that  time  show  a  poleward 
expansion  of  the  equatorial  floras  of  that  time,  so  that  in  south- 
eastern North  America  we  find  few  temperate  types  and  no  tulip- 
trees.  They  are  found,  however,  in  British  Columbia,  Greenland, 
Iceland,  and  England  during  the  later  Eocene.  The  Oligocene 
records  which  follow  those  of  the  Eocene  have  furnished  no  repre- 
sentatives of  the  tulip-tree,  but  well  marked  Miocene  forms,  repre- 
senting two  or  three  species  are  found  in  Italy,  Switzerland,  and 
Bohemia.  None  have  been  discovered  in  the  Miocene  or  Pliocene 
floras  of  North  America,  but  neither  of  these,  and  especially  that 
of  the  Pliocene  is  at  all  well  known. 

There  were  at  least  three  species  still  surviving  in  Europe  during 
Phocene  time  and  immediately  preceding  the  Glacial  period  (figs. 
6,  7).  These  were  found  in  Italy,  France  and  Holland,  and  their 
remains  comprise  both  leaves  and  characteristic  fruits  in  the  last 
two  areas.  Those  from  Holland  cannot  be  distinguished  from  the 
still  existing  American  tulip-tree,  which  adds  another  item  to  the 
long  array  of  facts  which  show  that  the  similarities  in  the  existing 
floras  of  North  America  and  eastern  Asia  and  the  dissimilarities 
shown  with  the  flora  of  Europe,  are  due  very  largely  to  the  havoc 
wrought  on  the  last  continent  by  the  intense  glaciations  combined 
with  the  peculiar  geography  and  topography  of  transverse  moun- 
tain chains  and  mediterranean  seas  which  largely  prevented  the 


180  TREE   ANCESTORS 

southward  retreat  of  the  forests.  Another  hnk  in  the  chain  of 
distribution  is  the  presence  of  fossil  leaves  Hke  those  of  the  existing 
species  in  the  Pliocene  of  the  Altai  mountains,  north  of  Tibet  in 
central  Asia.  The  extremely  sHght  differences  between  Liriodcn- 
dron  tulipifera  of  southeastern  North  America  and  Liriodendron 
chinensis  of  southwestern  China  probably  date  from  PHocene  time. 
Finally  in  Pleistocene  time  we  find  the  fossil  fruits  and  leaves  of 
the  existing  American  form  in  Maryland,  North  Carolina  and 
Alabama. 


CHAPTER  XVII 

The  Sweet  or  Red  Gum  and  Witch  Hazel 

The  sweet  gum  belongs  to  a  family,  often  called  the  witch  hazel 
family  (Hamamelidaceae),  whose  present  geographical  distribution 
is  of  remarkable  interest.  The  family  comprises  19  genera  in  all 
and  about  50  living  species,  and  no  less  than  9  of  these  genera  are 
monotypic,  that  is  to  say,  they  are  each  represented  by  but  a 
single  existing  species. 

Monotypic  genera  are  either  geologically  old  or  else  very  modern, 
that  is,  their  single  species  may  have  been  recently  evolved  or  it 
may  represent  the  last  remaining  descendant  of  a  long  and  now 
extinct  hne,  and  it  is  usually  possible  to  get  some  idea  as  to  which 
of  these  categories  we  are  dealing  with  by  a  consideration  of  the 
present  geographical  distribution  of  the  different  members  of  a 
plant  family.  In  the  case  of  this  family  12  of  the  19  genera  are 
confined  to  Asia,  1  is  prevailingly  Australian,  3  are  African  and  3 
are  confined  to  Asia  and  southeastern  North  America. 

Both  the  sweet  gum  and  the  witch  hazel  belong  to  this  last 
category,  their  present  range  being  shown  approximately  on  the 
accompanying  sketch  map  (fig.  39).  It  is  obvious  that  a  distri- 
bution such  as  this  indicates  that  the  family  to  which  they  belong 
had  an  extended  geological  history  and  that  the  particular  genera 
once  flourished  in  regions  that  connect  the  present  discontinuous 
occurrences.  The  only  alternative  is  to  suppose  that  the  present 
disconnected  areas  of  distribution  represent  special  creations — which 
is  absurd,  or  to  suppose  that  the  same  genus  originated  independ- 
ently on  different  continents,  which  is  almost  equally  absurd.  The 
details  of  the  geological  history  of  the  witch  hazel  family  are  for 
the  most  part  unloiown  because  of  the  imperfection  of  the  geological 
record. 

THE   S\^^EET  OR  RED  GUM 

No  part  of  the  Temperate  Zone  can  compare  with  southeastern 
North  America  in  the  brilliancy  of  autumnal  fohar  display  and  a 

181 


182  TREE    ANCESTORS 

considerable  part  of  this  is  due  to  the  sweet  gum,  whose  leaves 
assume  a  variety  of  shades  ranging  from  rich  yellow  through  carmine 
to  wine  red. 

Although  the  modem  sweet  gum  rivals  the  red  maple  or  the  dog- 
wood in  the  brilHancy  of  the  autumnal  tints  of  its  star-shaped 
leaves,  it  was  considered  practically  worthless  as  a  wood  until 
within  the  past  few  years,  owing  chiefly  to  its  tendency  to  warp 
and  twist.  It  was  formerly  left  standing  in  logging  operations 
and  when  land  was  cleared  for  agricultural  purposes,  the  sweet 
gum  was  girdled  and  left  to  rot.  But  times  and  opinions  change 
and  the  demand  for  the  wood  has  increased  rapidly  since  about  the 
year  1900. 

Not  only  does  the  heartwood  make  a  most  attractive  interior 
finish,  especially  for  panels,  doors  and  woodwork  in  its  natural 
color — abroad  it  is  often  called  satin  walnut — but  it  takes  stain 
so  well  that  it  is  often  made  into  mahogany,  oak  and  walnut  furni- 
ture. Sapwood  and  the  common  grades  go  into  boxes,  cheap 
furniture,  flooring,  staves,  etc.  There  is  a  large  export  trade  in 
the  heartwood,  possibly  as  much  as  50  per  cent  of  the  supply  going 
to  England,  France  and  Germany,  where  its  beauty  for  interior 
finishing  was  recognized  earlier  than  it  was  in  this  country. 

The  sweet  gum  occasionally  grows  to  a  height  of  150  feet  and 
a  diameter  of  5  feet.  Such  dimensions  are,  however,  unusual  and 
the  average  diameter  of  large  trees  is  perhaps  30  to  36  inches, 
indicating  a  normal  age  of  from  150  to  350  years,  the  size  being 
dependent  on  the  habitat.  The  trees  of  the  rich  bottoms  of  the 
south  Atlantic  Coastal  Plain  grow  much  faster  than  those  of  the 
lower  Ohio  valley.  The  stem  is  straight  and  columnar  and  until 
the  height  growth  is  attained  the  high  trunk  and  conical  crown 
make  it  resemble  a  conifer.  After  reaching  its  height  growth  it 
branches  freely  and  the  crown  becomes  rounded  and  spreading. 
Its  deeply  furrowed  bark  and  cork  winged  twigs  are  famihar  to 
every  explorer  of  swamps  in  our  southern  states. 

The  earliest  popular  nam.e,  sweet  gum,  doubtless  originated 
from  the  local  use  for  chewing  of  the  sweetish  gum  obtained  from 
the  tree.     The  later  name,  red  gum,  refers  to  the  reddish  brown 


THE    SWEET   OR   RED    GUM   AND   WITCH  HAZEL 


183 


color  of  the  heartwood  and  its  use  has  become  increasingly  com- 
mon since  the  decorative  qualities  and  commercial  possibilities 
of  the  wood  have  come  to  be  appreciated.  It  might  be  stated 
parenthetically  that  the  red  gum  is  not  related  to  the  black,  cotton 
and  tupelo  gums  so  common  in  similar  situations  throughout  the 
southeastern  United  States,  which  belong  to  the  genus  Nyssa  and 
are  related  to  the  dogwood. 


Fig.  39.  Sketch  Map  Showing  Present  Range  (black  areas)  and  Fossil 
Occurrences  of  the  Sweet  Gum  (solid  black  circles) 


The  red  gum  belongs  to  the  genus  Liquidambar,  a  name  derived 
from  the  latin  for  amber  colored  gum  in  allusion  to  the  balsamic 
exudation  or  gum  which  it  yields.  The  tree  is  a  native  from  south- 
western Connecticut  to  southeastern  Missouri  and  southward  to 
peninsular  Florida  and  eastern  Texas.  It  reappears  in  a  closely 
related  form  known  as  the  variety  mexicana  in  the  uplands  of 
central  and  southern  Mexico  and  the  highlands  of  Guatemala. 


184  TREE   ANCESTORS 

While  its  range  is  extensive  and  its  habitat  varied  it  reaches  the 
largest  size  and  commercial  possibilities  in  the  rich  bottom  lands 
of  mixed  hardwoods  in  the  maritime  districts  or  coastal  plain  of 
our  southern  States  from  the  valley  of  the  Great  Pedee  in  South 
Carolina  to  the  valley  of  the  Trinity  River  in  Texas,  and  northward 
along  the  bottoms  of  the  Mississippi,  Arkansas,  Tennessee  and 
Ohio.  In  the  more  northern  part  of  its  range  it  inhabits  swamp 
borders  and  low  wet  swales. 

There  are  at  least  three  additional  existing  species  of  Liquidam- 
bar — one  Liqiddamhar  macrophylla  Oersted,  found  in  the  mountains 
of  Central  America,  while  the  other  two  are  Asiatic.  Liquidamhar 
formosana  Hance  is  found  on  the  Island  of  Formosa  and  in  southern 
China,  and  the  other  separated  from  it  by  the  whole  breadth  of  the 
Asiatic  continent,  is  found  in  a  limited  area  in  the  mountains  of 
southwestern  Asia  Minor.  The  last  was  named  Liquidamhar  orien- 
talis  by  Miller  and  is  the  source  of  the  liquid  storax  of  commerce. 

This  disconnected  distribution  of  the  existing  species  of  Liquid- 
amhar, which  can  be  better  appreciated  by  a  glance  at  the  accom- 
panying map,  figure  39,  is  a  sure  indication  of  an  ancient  lineage 
and  a  former  occupation  of  the  intervening  areas  where  it  is  now 
extinct.  If  the  sweet  gum  stood  alone  in  having  such  a  remarkable 
range  its  interest  would  seem  much  greater,  but  since  the  days  of 
Asa  Gray's  American  Association  address  we  have  become  accus- 
tomed to  many  similar  ties  across  the  departed  ages  that  formerly 
connected  and  now  explain  the  near  kin  found  in  Asia  and  North 
America,  exemphfied  also  by  the  magnoHa,  sassafras,  coffee-bean 
and  tulip-tree. 

Turning  to  the  fossil  record  we  find  that  about  20  extinct  species 
of  Liquidamhar  have  been  described.  The  oldest  of  these,  Liquid- 
amhar integrif alius,  described  by  Lesquereux  from  the  Upper 
Cretaceous  Dakota  sandstone  of  Kansas  and  subsequently  identi- 
fied from  Canada,  Texas  and  South  America,  cannot  be  looked  upon 
as  the  Abraham  of  the  race  of  gums  for  unfortunately  for  our  story 
its  coriaceous  and  entire-margined  leaves  are  not  those  of  a  Liquid- 
amhar but  probably  represent  a  species  of  Stercuha — a  tropical 
genus  of  trees  that  was  very  common  in  Upper  Cretaceous  times 


THE    SWEET   OR   RED    GUM   AND   WITCH  HAZEL  185 

throughout  the  Northern  Hemisphere.  The  same  comment  apphes 
to  an  early  Eocene  form  described  from  France  by  Watelet,  a 
student  of  the  fossil  floras  of  the  Paris  basin. 

The  oldest  known  authentic  form  is  found  in  the  upper  Eocene 
in  Greenland,  Alaska  and  Oregon.  This  hints  at  the  Arctic  region 
as  the  original  home  of  the  genus — a  not  improbable  hypothesis, 
although  one  for  which  the  evidence  is  not  conclusive,  since  the 
vast  and  almost  unknown  expanse  of  Asia  cannot  be  left  out  of  the 
reckoning.  What  is  more  remarkable  is  the  fact  that  these  an- 
cestral gums  of  three  or  more  miUion  years  ago  and  all  of  their 
numerous  descendants  are  so  hke  the  sweet  gimis  of  today.  They 
had  the  same  palmately  lobed  and  variable  leaves  with  finely 
toothed  margins,  and  this  resemblance  extends  even  to  the  consist- 
ency of  the  leaves.  Today  in  our  southern  rivers  the  sweet  gum 
leaves  are  the  first  to  decay  when  they  fall  in  the  water  and  similarly, 
in  the  Pleistocene  river  deposits  the  gum  leaves  are  rarer  and  nearer 
dissolution  than  the  leaves  of  their  associates.  Judging  by  their 
usually  fragmentary  condition  in  the  older  rocks  this  characteristic 
was  as  true  then  as  now. 

Let  us  emphasize  then  the  first  landmark  in  the  history  of  the 
sweet  gum,  namely,  that  the  oldest  known  authentic  species  occurs 
in  the  late  Eocene  of  the  far  North  and  on  our  Pacific  coast  in 
Oregon  and  Alaska. 

Following  the  Eocene  is  the  period  of  earth  history  known  as 
the  Oligocene,  and  it  is  a  striking  commentary  on  the  imperfection 
of  the  geological  record  that  the  only  known  Ohgocene  species  of 
gum  is  recorded  from  Italy.  This  is  not  quite  as  bad  as  it  seems 
when  it  is  recalled  that  we  know  nothing  of  the  Ohgocene  history 
of  Asia  and  that  in  North  America  the  Ohgocene  was  a  time  of 
continental  mountain  basin  and  plains  deposits  throughout  the 
west  and  of  tropical  marine  deposits  along  the  southern  coasts, 
in  neither  of  which  are  to  be  found  many  traces  of  the  terrestrial 
vegetation  of  that  time. 

The  Oligocene  was  followed  by  Miocene  times  and  these  fortu- 
nately are  not  so  chary  with  their  evidence.  About  9  species  of 
sweet  gum  are  recorded  from  Miocene  rocks,  most  of  them  sur- 


186  TREE    ANCESTORS 

prisingly  like  the  modem  gum.  There  are  species  from  Japan 
on  the  east  and  from  southwestern  Asiatic  Russia  on  the  west. 
The  European  records  are  innumerable  and  widely  distributed 
and  the  American  records  include  Oregon  and  Colorado.  If  the 
reader  will  turn  to  the  accompanying  plate  the  resemblance  of 
these  ancient  flowers,  fruits  and  leaves  to  those  of  today  will  be 
at  once  apparent.  These  figures  are  taken  for  the  most  part 
from  the  wealth  of  remains  preserved  in  the  tiny  Miocene  Lake  of 
Oeningen  on  the  Swiss  border  of  Baden,  and  the  leaves  show  the 
same  variation  of  three,  four,  five,  or  more  lobed  forms  such  as 
can  be  matched  today  in  any  Southern  swamp. 

The  Miocene  was  followed  by  the  Phocene  and  the  gums  were 
stiU  cosmopolitan  in  the  Northern  Hemisphere  so  that  it  is  easy  to 
see  why  their  distribution  is  what  we  find  it  to  be  at  the  present 
time.  Pliocene  giuns  have  been  found  at  very  many  localities 
throughout  central  and  southern  Europe  as  well  as  on  our  Atlantic 
coast,  I  have  reproduced  a  worn  gum  ball  collected  from  the 
Pliocene  deposits  along  the  Main  River  in  Germany  on  the  accom- 
panying plate,  and  the  fruits  found  in  the  late  Pliocene  of  Holland 
are  indistinguishable  from  those  of  the  existing  species  of  Asia 
Minor. 

The  Pliocene  was  followed  by  the  Pleistocene  or  Glacial  time  and 
the  gums  found  fossil  in  this  comparatively  recent  geological  period 
include  traces  of  the  existing  Formosa  and  south  China  species, 
which  then  still  flourished  in  Japan,  and  the  abundant  leaves  and 
fruits  of  the  existing  red  gum  which  have  been  found  in  West  Vir- 
ginia, North  Carolina  and  Alabama.  A  leaf  and  fruit  from  the 
Pleistocene  swamp  deposits  along  the  Neuse  River  in  North  Caro- 
lina are  shown  on  the  plate. 

That  the  gums  which  were  so  abundant  throughout  Europe  in 
the  late  Tertiary  should  have  been  entirely  exterminated  by  the 
glacial  conditions  while  they  survived  in  North  America  and  Asia 
seems  strange  but  is  readily  understood  when  it  is  recalled  that 
high  mountains  and  seas  from  the  Pyrenees  to  the  Caucasus  made 
it  impossible  for  the  gums  to  escape  southward  to  more  genial 
climes  and  to  return  to  the  northward  again  when  the  cold  stages 


Fig.  40.  Some  Fossil  Leaves  and  Fruits  of  the  Sweet  Gum  (About  | 
Natural  Size) 

1,  2,  3.  Variously  lobed  leaves  and  fruit  of  Liquidambar  europacum  Al.  Br., 
from  the  late  Miocene  of  Baden. 

4,  5,  6.  Fruits  of  Liquidambar  pliocaenicum  Gejder  from  the  upper  Pliocene 
Brown  Coal  of  Germany. 

7,8.  Yrmt  din6.\ca.lol  Liquidambar  styraciflua'Lmn.,  from  the  Pleistocene  of 
North  Carolina. 

187 


188  TREE    ANCESTORS 

were  past,  as  was  possible  in  both  Asia  and  North  America.  The 
gum  was  only  one  of  the  many  forest  trees  of  the  European  Tertiary 
that  met  this  fate.  The  witch  hazel,  tulip-tree,  hickory,  walnut, 
magnolia,  and  many  others  shared  the  same  misfortune.  By  way 
of  contrast  with  the  present  distribution  of  the  sweet  gum  the 
accompanying  map  shows  the  Tertiary  occurrences,  thus  illus- 
trating something  of  the  past  history  as  it  has  just  been  related. 
The  record  of  the  sweet  gum  ancestry  does  not  go  back  so  far 
nor  is  it  as  detailed  as  that  of  many  of  our  forest  trees,  but  it  does 
cover  several  million  years  and  all  of  the  continents  of  the  Northern 
Hemisphere,  and  it  is  surely  impressive  when  we  recall  that  while 
we  have  collected  the  gum  balls,  as  the  fruits  are  commonly  called, 
admired  the  shape  of  the  leaves  and  their  autumnal  tints,  it  re- 
mained for  the  twentieth  century  to  discover  the  beauty  of  the 
wood  and  utilize  it  for  interior  finishing. 

THE  WITCH  HAZEL 

The  witch  hazel  is  closely  related  to  the  sweet  gum  but  is  sharply 
contrasted  with  it  in  size,  in  leaf  habit,  in  flowers  and  fruits.  It  is 
small  and  elfish  of  stature,  with  zig-zag  branches,  coarse  promi- 
nently veined  simple  leaves,  bilocular  woody  capsules  with  large 
bony  seeds,  and  fringe-like  bright  yellow  flowers.  Blooming  in  the 
winter  it  is  a  favorite  topic  for  discussion  whether  the  witch  hazel 
is  the  last  flower  of  fall  or  the  first  flower  of  spring.  The  persis- 
tence of  the  fruit  of  the  previous  season  until  the  flowering  time 
comes  around  again  has  suggested  the  scientific  name  of  the  genus 
Hamxamelis,  derived  from  the  greek  words  dfia,  \vith,  and  nfjXov, 
fruit. 

The  witch  hazel  is  an  altogether  different  plant  from  the  Old 
Saxon  witch  or  wych  hazel,  a  name  appHed  to  the  common  Euro- 
pean hazel  nut  which  was  Thor's  tree  and  a  magic  tree  as  well. 
Opinions  differ  as  to  the  origin  of  the  fact  that  the  twigs  were  long 
reputed  to  have  magic  properties  as  divining  rods — not,  however, 
for  the  discovery  of  witches,  but  to  locate  water,  oil  or  precious  min- 
erals. Others  see  the  origin  of  the  name  in  the  once  considered 
mysterious  bombardment  of  seeds  from  the  persistent  fruits.     When 


THE    SWEET   OR   RED    GUM  AND   WITCH   HAZEL  189 

the  yellow  pennants  of  the  witch  hazel  are  uncoiled  and  the  Novem- 
ber woods  are  tinged  with  a  yellow  halo  by  the  millions  of  crinkly 
petals,  last  seasons  woody  capsules  are  opened  and  loaded  and 
ready  to  bombard  the  loiterer  in  the  woods  with  their  doubled 
barrelled  load  of  hard  bony  seeds.  With  the  contraction  of  the 
walls  of  the  capsule  in  drymg  the  seeds  are  suddenly  and  forcibly 
expelled  a  distance  of  a  score  of  feet  or  more. 

There  are  three  existing  species  of  witch  hazel  and  their  distri- 
bution confirms  the  story  learned  from  that  of  the  sweet  gum. 
Our  North  American  form  ranges  from  the  maritime  provinces  of 
Canada  westward  up  the  St.  Lawrence  Valley  through  southern 
Ontario  to  Wisconsin  and  eastern  Nebraska,  and  southward  to 
northern  Florida  and  eastern  Texas.  It  thus  extends  much  farther 
north  than  the  sweet  gum  and  unlike  the  latter  it  reaches  its  largest 
size  on  the  slopes  of  the  higher  AUeghanies  in  the  Carolinas.  The 
wood  is  too  small  to  be  of  any  particular  use.  The  witch  hazel  is, 
however,  often  cultivated  as  an  ornamental  plant  in  our  northern 
States  and  in  northern  and  western  Europe,  because  of  its  odd 
habit  of  blooming  in  the  fall  and  winter,  a  habit  shared  by  the 
oriental  species.  The  bark  and  leaves  are  slightly  astringent  and 
although  without  any  known  essential  properties  are  largely  used 
in  homeopathic  practice,  and  the  extract  made  by  distilling  the 
bark  in  dilute  alcohol  is  extensively  sold  as  a  toilet  water. 

The  two  other  existing  species  of  witch  hazel  are  Asiatic — one, 
Hammelia  japonica  S.  &  Z.  being  found  in  the  mountains  of 
Japan  (Kiusiu  and  Nippon)  and  southern  China  (Kiangsi  and  Hu- 
peh).  Thus  all  the  witch  hazels  are  essentially  small  mountain 
trees  or  shrubs  and  not  bottom  dwellers  like  the  sweet  gum. 

Although  we  are  sure,  from  their  present  distribution,  that  the 
witch  hazels  of  today  are  the  relics  of  an  ancient  line,  we  know  little 
of  their  geological  history.  In  the  mid-Cretaceous  of  North 
America  a  number  of  leaves  have  been  found  which  have  been 
described  under  the  name  of  Hamamelites  (Saporta).  Some  of 
these  are  very  like  witch  hazel  leaves  but  whether  they  are  veritable 
witch  hazels  or  represent  some  other  members  of  this  family  it  is 
impossible  to  determine  conclusively.     Other  related  forms  occur 


190  TREE   ANCESTORS 

in  the  early  Eocene  of  Belgium,  France  and  Montana.  A  petrified 
wood  that  is  closely  related  to  if  it  is  not  true  wdtch-  hazel  wood 
(Hamamelidoxylon)  has  been  described  from  the  mid-Cretaceous 
of  France  and  flowers  (Hamamelidanthium)  are  preserved  in  the 
Baltic  amber  (Lower  Oligocene).  Finally  unmistakable  witch 
hazel  leaves  occur  in  the  Phocene  of  the  Auvergne  (Cantal)  so  that 
we  know  that  the  witch  hazel  was  present  in  Europe  in  pre-glacial 
times  although  it  became  entirely  extinct  on  that  continent  during 
the  period  of  glaciation. 


CHAPTER  XVIII 

Locust,  Coffee-bean  and  Red-bud 

A  consideration  of  the  locust^  and  its  allies  introduces  us  to  one 
of  the  largest  alliances  of  flowering  plants,  popularly  known  as  the 
Leguminosae,  and  now  divided  by  botanists  into  four  families. 
These  are  the  acacia  or  mimosa  family  (Mimosaceae) ,  the  senna 
family  (Caesalpiniaceae),  the  krameria  family  (Krameriacece),  and 
the  pea  or  bean  family  (Papilionaceas) .  Among  these  there  is  a 
well  marked  floral  progression  from  the  first,  with  its  regular 
flowers,  to  the  last,  with  its  butterfly-hke  blossoms.  The  first 
two  families  are  very  old  geologically  and  are  largely  arborescent 
foims  of  the  Tropical  Zone,  many  species  of  which  have  been  found 
fossil  in  the  Tertiary  deposits  of  our  southern  States.  The  last 
two  families,  on  the  other  hand,  are  mainly  herbaceous  forms 
dwelling  outside  the  tropics,  and  both  have  probably  attained 
their  maximum  of  variation  in  the  Temperate  Zone  since  the  in- 
auguration of  the  Pleistocene  glaciation. 

A  large  number  of  leguminous  plants  furnish  most  important 
food  or  forage  crops  (peas,  beans,  lentil,  peanut,  tamarind,  alfalfa, 
clover,  etc.)  or  are  utilized  in  medicine  (senna,  licorice,  etc.)  or 
other  arts  (indigo,  logwood,  gum  tragacanth,  gum  arable,  copaiba 
gum,  etc.).  The  habit  of  many  of  the  Leguminosae  of  abstracting 
nitrogen  from  the  air  by  means  of  root  bacteria  makes  them  of 
especial  interest  in  these  days  of  the  rapid  exhaustion  of  natural 
nitrates.  Many  tropical  Leguminosae  are  important  timber  trees 
(brazil  wood,  iron  wood,  violet  wood,  etc.)  but  outside  of  local  uses 
the  world's  markets  know  but  a  few  and  these  are  found  in  the 
cabinet  maker's  rather  than  in  the  lumber  trade,  and  scarcely  any 
awaken  a  concept  in  the  popular  mind  unless  it  be  rosewood 

^  This  is  not  the  locust  tree  of  southern  Europe,  which  is  the  carob,  Cecratonia 
siliqua,  a  member  of  the  Caesalpiniaceae.   • 

191 


Fig.  41.  Some  Fossil  Leaves  and  Pods  of  tiie  Red  bud  (About  ^ 
Natural  Size) 

1,  2.  Leaf  and  pod  of  Ccrcis  antiqua  Sap.  from  the  Oligocene  of  France. 
3,  4.  Leaf  and  pod  of  Ccrcis  virgi liana  Mass.  from  the  upper  Miocene  of 
Italy. 

5,  6.  Leaves  of  Ccrcis  tournoucri  Sap.  from  the  upper  Oligocene  of  France. 

7.  Leaf  of  Ccrcis  wilcoxiuna  Berry  from  the  lower  Eocene  of  Tennessee. 

8.  Leaf  of  Cercis  canadensis  Linn,  from  the  Pleistocene  of  North  Carolina. 

9.  9  a.  Leaf  and  pod  of  Cercis  s  Hi  quasi  rum  Linn,  from  the  Pleistocene  of 
France. 

192 


LOCUST,    COFFEE-BEAN   AND   RED-BUD  193 

(Dalbergia),  a  tree  of  the  pea  family  which  furnishes  such  an  In- 
comparably handsome  cabinet  wood. 

There  are  about  500  genera  and  10,000  existing  species  of  Legu- 
minosas,  of  which  only  17  genera  with  about  32  species  attain  to 
the  stature  of  trees  within  the  limits  of  the  United  States,  and  the 
bulk  of  these  are  confined  either  to  the  subtropical  coastal  belt  of 
Florida  or  to  the  arid  southwest.  The  only  tree  forms  that  are 
widely  familiar  in  the  eastern  States  are  the  Judas-tree  or  red-bud 
(Cercis),  the  Kentucky  coffee  tree  (Gymnocladus),  and  the  honey 
locust  (Gleditsia)  of  the  family  Caesalpiniaceae  and  the  locust 
(Robinia)  of  the  family  Papilionacese,  so  that  our  attention  in 
the  present  chapter  will  be  confined  to  these  four  trees. 

THE    LOCUST    (rOBINIA) 

The  black  locust,  often  called  the  yellow  locust  because  cf  its 
yellowish  brown  heart  wood  and  yellowish  white  sapwood,  is  the 
type  of  the  genus  Robinia,  so  named  by  Linnaeus  in  honor  of 
Jean  and  Vespasian  Robin  who  introduced  it  into  Europe  at  the 
end  of  the  sixteenth  century,  at  which  time  the  former  was  in  charge 
of  the  Garden  of  the  Louvre.  The  specific  name  which  Linnaeus 
gave  this  species,  pseudacacia,  commemorates  in  latinized  form 
the  common  European  name  of  false  acacia  by  which  this  North 
American  tree  has  usually  been  known  abroad. 

Its  natural  range  extends  from  Pennsylvania  to  Georgia  and 
westward  to  Iowa  but  it  has  been  extensively  naturalized  on  our 
western  prairies  as  well  as  on  the  plains  of  Hungary.  Perhaps  no 
American  tree  was  so  extensively  planted  in  Europe,  and  our  colo- 
nists also,  in  the  period  immediately  following  the  Revolution, 
valued  it  highly  both  for  its  timber  and  for  its  beneficial  efifect  upon 
soils.  In  Revolutionary  France  May  6  was  consecrated  to  the 
locust. 

It  is  a  medium  sized  tree  and,  while  it  sometimes  reaches  a 
height  of  90  feet  and  a  trunk  diameter  of  4  feet,  the  average  tree 
branches  early  and  tops  irregularly  and  is  not  over  50  or  60  feet 
tall  and  about  20  inches  in  trunk  diameter.  The  leaves,  in  com- 
mon with  nearly  all  the  other  members  of  the  leguminous  aUiance, 


194  TREE    ANCESTORS 

are  what  are  knowTi  as  compound,  that  is  they  consist  of  many- 
separate  leaflets.  There  are,  in  the  locust,  from  7  to  9  opposite 
pairs  of  elliptical  slightly  stalked  leaflets  and  an  odd  one  at  the  end 
terminates  the  slender  stalk  of  the  leaf,  which  is  from  8  to  14  inches 
in  length.  At  the  base  of  the  leaf-stalk  a  pair  of  short  subulate 
stipules  or  accessory  leaflets  soon  become  transformed  into  straight 
or  shghtly  recurved  spines  which  persist  for  many  years,  often 
becoming  an  inch  or  more  in  length. 

The  flower  clusters,  which  appear  after  the  leaves  toward  the 
end  of  May,  convert  the  tree  into  a  creamy  white  bower  of  incense, 
since  they  are  filled  with  fragrant  nectar.  The  fruit,  which  ripens 
late  in  the  autumn,  is  a  red-browTi  pod,  3  to  4  inches  long  and  ^ 
an  inch  wide  with  4  to  8  smooth  brown  seeds,  which  are  shed  from 
the  opened  pods  during  the  winter  or  early  spring  before  the  pods 
let  go  their  hold  on  the  parent  tree.  The  locust  is  one  of  our  most 
prolific  trees  in  sending  out  sprouts  from  the  roots,  hence  a  tree 
will  spread  rapidly  and  is  difficult  to  eradicate.  It  grows  rapidly 
when  young  and  thrives  in  the  fertile  soils  of  the  Appalachian 
Mountain  valleys,  but  will  also  make  a  good  growth  on  sandy  or 
rocky  soils. 

The  wood  is  heavy,  exceedingly  hard  and  strong,  and  very 
durable  in  contact  with  ground  or  air,  hence  it  is  highly  valued 
for  fence  posts  and  rails,  cross  arms  and  insulator  pins  for  telephone 

Pig.  42.  Some  Fossil  Locusts  and  Coffee  Beans  (About  f  Natural  Size) 

1,  2,  3.  Leaflets  and  pod  of  the  existing  Rohinia  pseudacacia  Linn. 

4.  Robinia  hesperidum  linger  from  the  upper  Miocene  of  Croatia. 

5.  A  probable  locust  leaflet  from  the  Upper  Cretaceous  of  South  Carolina. 

6.  7,  8.  Leaf  and  pods  of  Rohinia  rcgeli  Heer  from  the  upper  Miocene  of 
Baden. 

9.  Another  locust  pod  from  the  upper  Miocene  of  Baden. 

10.  A  leaflet  of  the  existing  Gymnocladus  dioecus  Koch. 

IL  Gymnocladus  casei  Berry  from  the  Miocene  of  Oklahoma. 

12.  A  leaflet  of  a  IMiocene  honey  locust,  Gleditsia  allemannica  Heer,  from 
Baden. 

13.  A  leaflet  of  the  existing  honey  locust. 

14.  15,  16.  A  thorn,  leaf  and  pod  of  a  honey  locust,  Gleditsia  Wesseli  Weber 
from  the  lower  Miocene  of  Germany. 


Fig.  42 
195 


196  TREE    ANCESTORS 

and  telegraph  lines,  carriage  hubs  and  similar  turnery,  tree  nails, 
etc.  It  is  also  valued  for  fuel  and  construction  purposes,  but  does 
not  enter  largely  into  the  general  lumber  industry  because  of  the 
scattered  supply  and  its  special  uses. 

A  tree  that  has  been  cultivated  for  so  long  a  time  has  naturally 
given  rise  to  numerous  horticultural  varieties  of  the  parks  and 
gardens.  There  are  also  6  or  7  additional  species  of  Robinia,  all 
confined  to  North  America  and  very  similar  to  the  preceding  except 
that  they  are  smaller  trees  or  even  shrubs.  The  only  one  of  these 
that  is  generally  kno^vn  is  the  clammy  locust,  Robinia  viscosa  Vent., 
which  may  be  readily  distinguished  by  the  lack  of  fragrance  of 
its  blossoms.  It  is  a  native  of  the  mountains  from  southwestern 
Virginia  to  Georgia,  but  has  been  extensively  planted  in  all  tem- 
perate countries  where  the  climate  is  not  prohibitive  and  has  be- 
come extensively  naturalized  east  of  the  Mississippi  as  far  north 
as  Massachusetts. 

The  rose  acacia,  Robinia  hispida  Linn,  of  the  southern  Appa- 
lachians, a  shrub  with  pink  or  purple  non-fragrant  blossoms;  and 
the  New  Mexican  locust,  Robinia  neo-mexicana  Gray,  a  shrub  or 
small  tree  of  the  mountain  valleys  of  Colorado,  New  Mexico, 
Arizona,  and  southern  Utah,  with  handsome  blossoms,  are  both 
favorites  outside  their  natural  limits  for  ornamental  planting  in 
both  this  country  and  western  Europe. 

The  geological  history  of  the  locust  is  beset  with  difficulties, 
the  leaflets  usually  becoming  detached  before  fossilization  and 
both  leaflets  and  pods  being  often  impossible  to  differentiate 
from  other  and  unrelated  leguminous  leaflets  and  pods.  Tliis 
difficulty  of  distinguishing  between  the  fossil  leaflets  of  the  various 
genera  of  Leguminosa^  has  led  paleobotanists  to  estabhsh  a  purely 
formgenus  known  as  Leguminosites  for  leaflets  of  this  sort  that 
cannot  be  identified  with  certainty  beyond  that  they  are  legumi- 
nous. Large  numbers  of  species  of  Leguminosites  ranging  in  age 
from  the  Upper  Cretaceous  through  the  Tertiary  are  known. 
Among  these  are  several  that  might  well  represent  an  Upper  Cre- 
taceous locust,  but  such  an  identity  is  not  conclusive.  Certain 
pods  from  the  top  of  the  Cretaceous  in  Colorado  have  been  referred 


LOCUST,    COFFEE-BEAN   AND   RED-BUD  197 

to  Robinia  but  since  this  genus  has  not  been  recognized  with  cer- 
tainty in  the  succeeding  Eocene  deposits  either  in  this  country  or 
elsewhere,  these  too  must  be  considered  questionable.  Two  species 
of  locust  have  been  recognized  in  the  Oligocene  of  Europe — one  in 
France  and  the  other  in  Italy.  It  is  in  the  Miocene,  however, 
that  the  locust  becomes  widespread  and  exceedingly  common. 
At  least  a  dozen  different  species  have  been  recognized  from  Euro- 
pean deposits  of  this  age  and  one  of  these  from  the  late  Miocene  of 
central  France  is  so  similar  to  the  existing  locust  of  North  America 
that  its  describer  is  disposed  to  consider  the  two  as  identical.  This 
form  continued  to  exist  in  the  European  area  in  Pliocene  times. 
A  well  marked  locust  has  also  been  found  in  the  deposits  of  the  lake- 
basin  at  Florissant,  Colorado,  but  no  other  North  American  Mio- 
cene form  has  been  discovered. 

In  addition  to  the  very  modern  looking  Pliocene  form  already 
mentioned  a  second  was  common  at  this  time  along  the  Mediter- 
ranean coast  of  southern  Europe  from  Spain  to  Slavonia.  There  is 
no  evidence  that  the  locust  survived  the  first  glaciation  in  Europe 
but  in  North  America  we  find  the  modern  species  in  the  Interglacial 
deposits  of  the  Don  Valley  in  Ontario  some  distance  north  of  its 
existing  range,  and  it  is  also  found  in  the  late  Pleistocene  of  Mary- 
land. 

THE  HONEY  LOCUST  (gLEDITSIA) 

The  black  locust  is  sometimes  called  the  honey  locust  in  New 
England  because  of  its  fragrant  nectar-bearing  blossoms.  The 
true  honey  locust  is,  however,  quite  another  tree  and  belongs  to 
the  family  Caesalpiniaceae,  Robinia  belonging  to  the  family  Papi- 
HonacejE. 

The  honey  locust  belongs  to  the  genus  Gleditsia,  sometimes 
spelled  Gleditschia  since  it  was  named  by  Linnaeus  in  1753  in 
honor  of  J.  T.  Gleditsch,  a  German  botanist.  Gleditsia  contains 
5  or  6  species  natives  of  eastern  North  America  and  Asia,  and  3  of 
these  are  found  in  the  United  States.  One,  Gleditsia  texana, 
Sargent,  is  confined  to  the  Brazos  River  Valley  in  Texas;  a  second, 
the  water  locust  Gleditsia  aguatica  Marsh,  is  found  in  our  southern 


198  TREE   ANCESTORS 

States;  and  the  true  honey  locust,  Glcditsia  triacanthos  Linnaeus, 
a  tall  graceful  tree,  ranges  from  Ontario  and  western  New  York 
to  Georgia,  Kansas  and  Texas. 

The  honey  locust  is  a  large  tree  75  to  140  feet  in  height  and  with 
a  trunk  2  or  3  and  occasionally  as  much  as  6  feet  in  diameter.  It  is 
exceedingly  graceful  in  habit  with  its  slender  spreading  and  some- 
what pendulous  branches  forming  a  broad  open  head.  This 
together  with  its  tiny  leaflets  gives  it  more  the  appearance  of  so 
many  of  the  tropical  species  of  Leguminosae  rather  than  of  a  tree 
of  the  Temperate  Zone,  and  it  is  consequently  a  general  favorite 
as  an  ornamental  and  shade  tree  in  all  countries  with  a  suitable 
cKmate. 

The  leaves  are  sometimes  slender  stalks  with  9  to  14  pairs  of 
oblong-ovate  leaflets  which  are  never  over  Ij  inches  long  and  \ 
inch  wide,  and  which  usually  have  a  slightly,  but  not  apparent, 
crenulate  margin.  More  usually  the  leafstalk  bears  from  4  to  7 
pairs  of  branches  each  with  8  to  12  pairs  of  leaflets,  which  are 
generally  under  an  inch  in  length  and  ^  inch  in  width.  Such  leaves 
in  which  there  is  on  odd  terminal  unpaired  leaflet  on  the  main 
stalk  or  the  branches  is  termed  even  pinnate.  Sometimes,  however, 
the  honey  locust  leaves  do  have  such  an  odd  terminal  leaflet,  and 
frequently  either  the  basal  or  the  terminal  part  of  the  leaf  stalk 
will  lack  subordinate  leaflet  bearing  branches  and  have  in  their 
place  somewhat  larger  leaflets  on  the  main  stalk  with  the  leaflet 
bearing  branches  in  the  middle  part  of  the  leaf  stalk.  The  stipules 
are  small  and  are  soon  shed  and  do  not  develop  into  spines  as  in 
the  black  locust.  Nevertheless  the  honey  locust  is  plentifully 
supplied  with  thorns.  These  are  large  and  much  branched  and 
are  not  superficial  (epidermal)  like  the  spines  of  the  black  locust 
but  are  true  abortive  branches  and  cannot  be  readily  detached 
except  by  cutting. 

The  flowers  appear  in  the  late  spring  after  the  leaves.  They 
are  not  especially  conspicuous  being  greenish-white  in  color,  but 
are  exceedingly  fragrant  and  abundantly  nectar-bearing.  They 
are  not  irregular  like  a  pea  blossom  as  are  those  of  the  black  locust, 
but  regular  and  polygamous,  i.e.,  some  are  pollen-bearing  and  some 


LOCUST,    COFFEE-BEAN   AND    RED-BUD  199 

seed-bearing.  The  pods  are  large  and  flattened,  bright  brown  or 
purphsh  in  color  when  mature,  and  are  always  more  or  less  curved 
and  twisted  as  they  contract  in  drying  during  the  autumn.  They 
are  from  5  to  18  inches  long  and  about  1^  Inches  wide.  The  space 
between  the  seeds  is  filled  with  a  sweet  succulent  pulp,  hence  the 
name  honey  shucks,  and  the  pods  do  not  split  open  when  the  seeds 
are  ripe.  The  wood  is  much  like  that  of  the  black  locust  and  is 
used  for  similar  purposes. 

The  water  locust  is  a  much  smaller  tree,  with  leaves  much  like 
those  of  the  honey  locust  but  with  somewhat  larger  leaflets,  which 
are  thicker  and  a  darker  green.  The  pods,  however,  are  not  much 
longer  than  wide  with  only  one  or  two  seeds  and  without  a  succu- 
lent pulp.  The  water  locust  is  an  inhabitant  of  river  bottoms  and 
swamps  and  attains  its  maximum  size  in  the  bottom  swamps  and 
along  stream  banks  in  Louisiana  and  Arkansas. 

No  representatives  of  the  honey  locust  can  be  recognized  with 
certainty  in  either  the  Upper  Cretaceous  or  the  Eocene,  although 
there  are  a  number  of  leguminous  leaflets  found  in  the  rocks  of 
both  of  these  periods  that  might  well  represent  its  ancestors,  in 
fact  a  genus  called  Gleditsiophyllum  found  in  both  the  Upper 
Cretaceous  and  the  Eocene  of  North  America  is  suggestively 
like  the  honey  locust. 

A  supposed  species  is  recorded  from  the  Oligocene  of  Europe 
and  there  are  a  number  of  undoubted  Miocene  species.  Seven 
or  eight  have  been  described,  one  occurring  on  the  east  coast  of 
Asia  and  the  others  all  confined  to  Europe,  where  they  are  known 
from  Greece  and  Hungary  to  France.  They  are  especially  abun- 
dant in  the  Miocene  woods  of  Switzerland  in  the  days  before  the 
formation  of  the  Alps  had  been  completed.  Pliocene  records  are 
wanting  in  both  this  country  and  Europe.  The  modem  species 
appears  in  the  early  Pleistocene  of  Kentucky  and  an  extinct  species 
is  recorded  from  the  Interglacial  deposits  of  the  Don  Valley  in 
Ontario. 


200  TREE  ANCESTORS 

THE  KENTUCKY  COFFEE-TREE   (gYMNOCL.ADUS) 

G>Tnnocladus  is  one  of  those  rather  numerous  and  unrelated 
genera  that  at  the  present  time  is  native  only  in  southeastern 
North  i\merica  and  southeastern  Asia,  and  like  the  Tulip-tree 
and  the  Sassafras  it  has  a  single  species  in  each  region,  scarcely 
distinguishable  from  one  another,  while  the  ancestral  stock  has 
become  extinct  in  the  intervening  areas.  Our  American  tree  is 
commonly  known  as  the  Kentucky  coflee-tree  or  coffee  bean,  since 
its  seeds  were  sometimes  used  as  a  substitute  for  coffee,  especially 
during  pioneer  and  Revolutionary  times.  It  is  also  called  the 
stump  tree  in  certain  localities  because  the  leafstalks  are  often 
shed  after  the  leaflets  and  their  large  size  makes  it  appear  that  the 
tree  is  shedding  its  twigs.  The  fresh  green  pulp  of  the  unripe 
pods  is  still  used  in  homoeopathic  practice  and  the  pulp  surrounding 
the  seeds  of  the  Chinese  species  is  detersive  and  is  widely  used  in 
its  native  land  as  a  substitute  for  soap. 

The  Kentucky  cofTee-tree  is  a  large  stately  tree  from  75  to  110 
feet  tall  with  a  trunk  from  2  to  3  feet  in  diameter,  which,  however 
generally  forks  to  form  three  or  four  main  stems  within  10  or  15 
feet  of  the  ground.  The  leaves  are  large,  particularly  on  vigorous 
saplings  and  may  measure  3  feet  in  length  by  2  feet  in  width.  They 
have  a  stout  leafstalk,  a  terminal  branch  and  from  2  to  4  pairs  of 
lateral  branches,  each  bearing  from  6  to  14  pairs  of  subsessile  ovate 
leaflets,  pink  at  first  and  turning  to  a  bronzy  green  at  maturity. 
The  stipules,  which  in  Robinia  become  spines,  are  foliaceous  and 
are  soon  shed.  Nor  does  the  coffee-tree  develop  thorns  like  its 
close  ally  the  honey  locust.  The  flower  clusters  are  large  but 
scarcely  conspicuous  except  in  the  young  trees.  The  flowers, 
while  sometimes  mixed  usually  have  the  pollen  bearing  ones  in 
separate  and  larger  clusters  than  the  seed  bearing  ones.  The 
pods  are  large  and  hard,  dark  reddish  brown  in  color,  and  are  some- 
times as  much  as  10  inches  long  and  2  inches  wide.  They  remain 
unopened  throughout  the  winter  and  contain  numerous  very  hard 
globular  seeds,  about  the  size  of  small  marbles,  imbedded  in  the 
sweet  pulp.     The  wood  is  strong  and  coarse  grained,  heav}^  but 


LOCUST,    COFFEE-BEAN   AND    RED-BUD  201 

not  hard.  Like  locust  wood  it  resists  decay  and  is  occasionally 
utilized  for  fence  posts,  rails,  ties  and  construction,  and  rarely 
for  cabinet  work.  The  shortness  of  the  butts  and  the  scattered 
growth  usually  render  the  tree  immune  from  the  lumberman. 

The  coffee-tree  prefers  rich  soil  and  occurs  sporadically  but 
nowhere  in  abundance  from  central  New  York  and  western  Penn- 
sylvania through  southern  Ontario  and  southern  Michigan  to  the 
valley  of  the  Minnesota  and  southward  to  middle  Tennessee  and 
southwestern  Arkansas.  It  penetrates  the  prairie  country  along 
the  bottoms  of  the  larger  streams  in  eastern  Kansas,  Nebraska  and 
Oklahoma.  It  is  frequently  planted  in  parks  in  the  eastern  United 
States  and  in  western  Europe. 

The  geological  history  of  this  tree  is  unfortunately  almost  en- 
tirely unknown.  As  it  occurs  at  the  present  time  in  both  Asia  and 
North  America  it  must  have  been  present  during  the  Tertiary  in 
the  intervening  region,  as  I  have  already  remarked.  This  implies 
its  presence  in  not  only  the  Arctic  region  but  in  northwestern  North 
America  and  very  probably  in  Europe.  Its  former  presence  on 
the  last  continent  has  not  been  definitely  proven,  however.  Sa- 
porta,  many  years  ago  described  leaflets  and  pods  from  the  basal 
Miocene  of  France  as  Gymnodadus  macrocarpa,  but  these  are 
usually  regarded  as  more  properly  referable  to  some  other  legumi- 
nous genus.  Squinabol  named  a  pod  from  the  Ohgocene  of  Italy 
Gymnodadus  novalensis  but  this  too  is  of  doubtful  identity.  An 
undoubted  fossil  form  has  been  found  in  North  America.  This  is 
Gymnodadus  casei  and  it  comes  from  the  late  Miocene  of  the  "pan- 
handle" region  of  Oklahoma.  It  was  much  like  the  modern  coffee- 
tree  and  is  of  interest  chiefly  in  showing  that  at  that  time  the 
western  range  of  the  genus  was  not  as  restricted  as  it  is  today. 

There  are  also  fossil  leaflets  that  appear  to  represent  a  European 
coffee-tree  found  in  deposits  in  central  France,  the  Auvergne,  of 
late  Miocene  age. 

THE   JUDAS-TREE    (CERCIS) 

Unlike  the  great  majority  of  leguminous  genera  the  different 
species  of  Cercis  have  simple  leaves.     These  are  cordate-orbicular 


202  TREE   ANCESTORS 

in  form,  glossy  green,  palmately  5  to  7  veined  and  arranged  in  a 
two-ranked  manner  on  the  long  shoots.  The  pods  are  small  and 
compressed,  lustrously  red  purple  in  color,  and  fall  in  the  late 
autumn  or  early  winter.  There  are  5  or  6  existing  species  of  Cercis 
although  the  majority  of  my  readers  will  be  famihar  with  only 
the  European  Judas-tree  or  its  very  similar  American  relative. 
In  addition  to  these  two  well  known  ornamental  trees  there  is  a 
third  species  in  Texas,  another  on  the  Pacific  coast  of  North  America 
and  two  or  three  more  in  southwestern,  central,  and  eastern  Asia. 
Thus  Cercis  is  another  genus  whose  distribution  suggests  the  same 
thoughts  as  did  the  distribution  of  Gymnocladus.  But  in  the  case 
of  the  former  more  links  in  the  chain  have  remained  until  modern 
times  and  its  distribution  today  suggests  what  may  have  been  and 
probably  was  the  distribution  of  Gymnocladus  in  Miocene  times. 

The  European  Judas-tree,  Cercis  siliquastrum  is  a  native  of  the 
south  of  France,  the  Spanish  peninsula,  Italy,  Greece  and  Asia 
Minor.  It  is  a  handsome  low  tree  with  a  flat  spreading  head, 
much  utilized  in  ornamental  plantings  throughout  Europe.  Its 
profuse  purplish-pink  flowers  appear  before  the  leaves.  They 
have  an  agreeable  acid  taste  and  are  sometimes  mixed  with  salads 
or  made  into  fritters. 

When  originally  described  the  Judas-tree  was  the  tree  of  Judea, 
from  its  supposed  origin  in  Palestine.  This  name  gradually  be- 
came transposed  into  Judas-tree  and  tradition  accounted  for  the 
latter  name  by  the  fact  that  it  was  this  tree  on  which  Judas  Iscariot 
hanged  himself.  The  tree  was  frequently  figured  by  the  herbal- 
ists, and  one,  Castor  Durante,  gives  a  woodcut  showing  Judas 
hanging  from  the  branches  thus  illustrating  the  popular  tradition. 

The  American  tree,  Cercis  canadensis,  is  much  like  its  European 
relative  in  every  way  and  like  the  latter  it  is  commonly  known  as 
the  Judas-tree,  particularly  in  ornamental  plantings,  for  which  it 
is  extensively  used  not  only  throughout  our  northeastern  states 
but  also  in  western  Europe.  In  its  natural  surroundings  it  is 
perhaps  more  often  known  as  the  red-bud,  and  is  one  of  the  strik- 
ing objects  of  the  early  almost  leafless  spring  woods,  its  masses  of 
purplish-pink  blossoms  close  to  the  branches,  contrasting  with  the 


LOCUST,    COFFEE-BEAN   AND   RED-BUD  203 

white  of  the  opening  dogwood  and  forming  splashes  of  bloom  in 
the  gray  woods.  In  the  latter  half  of  March  the  traveller  through 
Virginia  and  the  Carolinas  can  scarcely  distinguish  from  the  train 
window  between  the  blooming  peaches  and  the  red-buds  of  the  door- 
yards. 

Our  Judas-tree  grows  naturally  from  the  valley  of  the  Delaware 
and  southern  Ontario  to  Tampa  Bay,  northern  Alabama,  Mississippi 
and  Texas,  and  extends  westward  along  the  bottoms  of  the  large 
streams  into  the  eastern  border  of  the  prairie  states.  It  is  said 
that  the  blossoms  are  sometimes  eaten,  although  I  have  never 
observed  this  custom.  In  the  days  before  the  prevalence  of  ani- 
line dyes  the  branches  were  sometimes  used  for  giving  wool  a  nan- 
keen color. 

The  members  of  this  genus  are  too  small  for  lumbering  and  the 
wood  has  no  special  uses  that  I  know  of,  consequently  we  are  not 
likely  to  be  deprived  of  the  striking  beauty  of  the  Judas-tree  as 
we  probably  should  if  the  wood  could  be  used  for  bobbins  or  lead 
pencils  or  boxes. 

Fortunately  in  the  case  of  the  Judas-tree  a  considerable  beginning 
has  been  made  in  tracing  its  geological  history,  although  the  in- 
evitable gaps  in  this  history  have  not  all  been  closed.  The  oldest 
known  forms  come  from  the  lower  Eocene  and  all  of  these,  three 
in  number,  are  North  American,  occurring  in  Tennessee,  Mississippi, 
Montana  and  Dakota — the  last  being  in  a  region  now  one  of 
prairies  and  bad  lands  far  removed  from  the  habitat  of  any  of  the 
existing  forms  and  showing  how  the  ancestral  Judas-trees  were 
enabled  to  migrate  across  North  America  in  the  more  humid  days 
that  preceded  the  development  of  the  prairie  type  of  country.  A 
middle  Eocene  species  occurs  at  Bournemouth  on  the  south  coast 
of  England  and  an  upper  Eocene  form  has  recently  been  described, 
associated  with  a  large  and  warm  climate  flora,  in  Hesse,  Germany. 
By  succeeding  Ohgocene  times  the  Judas-tree  had  appeared  at 
additional  localities  in  Europe  where  a  very  characteristic  form 
is  found  in  southeastern  France  in  the  lower  Oligocene  and  a  second 
French  species  occurs  at  a  somewhat  later  stage  of  the  Oligocene. 


204  TREE   ANCESTORS 

We  are  %vithout  information  as  to  whether  Cercis  came  down 
from  the  north  into  both  North  America  and  Europe  or  whether 
America  was  its  original  home  and  it  spread  across  the  land  bridge 
in  the  region  of  Behring  Sea  into  Asia  and  thence  into  Europe. 
Personally  I  favor  the  interpretation  that  the  vast  and  paleobotani- 
cally  almost  unkno\vn  continent  of  Asia  was  the  original  home  of 
the  genus  from  which  it  spread  westward  into  Europe  and  eastward 
across  the  Behring  land  bridge  into  North  America.  If  this  is 
the  true  story  then  this  migration  must  have  taken  place  during 
Upper  Cretaceous  times  even  though  we  have  not  yet  found  Cercis 
in  the  abundant  Upper  Cretaceous  floras,  for  it  is  present  in  the 
lower  Eocene  of  our  Gulf  States  and  in  the  middle  Eocene  of  the 
south  of  England  and  a  journey  from  Asia  would  have  required 
a  very  long  time. 

The  Miocene  was  pre-eminently  the  period  of  hardwood  forests, 
and  the  ancestral  Judas-trees  seem  to  have  reached  the  zenith  of 
their  differentiation  and  their  most  extensive  range  during  these 
ages  that  succeeded  the  OHgocene.  Although  Asia  remains  an 
unknown  area  we  have  a  glimpse  of  a  small  species  preserved 
in  the  volcanic  ash  beds  of  the  Florissant  lake  basin  in  the  heart  of 
the  Colorado  Rockies,  and  a  second  species  in  Nevada.  No  less 
than  5  species  are  already  known  from  Miocene  Europe,  where 
they  are  represented  as  fossils  by  both  leaves  and  pods.  It  is 
especially  interesting  to  note  that  one  of  these  from  the  late  Miocene 
of  Italy  and  another  closely  related  form  of  the  same  age  in  France 
are  directly  ancestral  to  the  existing  European  Judas-tree,  while 
a  second  French  species  {Cercis  ameliae  Saporta)  from  the  older 
Miocene  of  France  seems  to  have  been  the  ancestor  of  the  existing 
Cercis  japonica  Siebold  of  eastern  Asia.  There  is  little  direct 
evidence  of  the  Judas-tree  during  the  succeeding  Ph'ocene  times. 
Since  it  occurs  both  before  and  after  the  Pliocene  in  North  America 
it  must  have  been  present  at  that  time.  In  Europe  a  single 
Pliocene  species  is  known  from  France. 

As  practically  everyone  knows,  the  Pleistocene,  which  succeeded 
the  Pliocene,  was  a  time  of  continental  ice  sheets  or  glaciers,  which 
played  havoc  with  the  floras  and  faunas,  particularly  in  Europe 


LOCUST,  COFFEE-BEAN  AND  RED-BUD  205 

because  of  the  combination  of  high  mountains  and  seas  along  its 
southern  border  which  effectually  barred  the  ebb  and  flow  of  life 
that  took  place  in  Asia  and  North  America  with  the  advance  and 
retreat  of  the  successive  ice  sheets.  During  the  maximum  extent 
of  the  ice  only  a  fraction  of  the  Northern  Hemisphere  was  covered 
and  Asia  was  largely  ice-free.  The  southern  hmit  of  the  ice  in 
Europe,  where  the  center  of  accumulation  and  dispersal  was  the 
Scandinavian  region,  was  the  German  plain.  Here  in  North 
America  the  easternmost  or  Labradoran  center  of  accumulation 
and  dispersal  extended  its  ice  fields  only  as  far  south  as  Staten 
Island  on  the  Atlantic  coast,  so  that  there  was  plenty  of  room  south 
of  the  ice  for  a  vast  forest  and  game  preserve  for  the  subsequent 
repopulation  of  the  more  northern  region. 

There  were  at  least  four  periods  of  glaciation  which  were 
separated  by  long  intervals  during  which  the  ice  disappeared 
except  in  the  far  North,  and  it  is  in  the  deposits  formed  during 
these  Interglacial  periods  that  we  find  the  fossil  remains  of  the 
Judas-tree.  Both  the  American  and  the  European  Judas-tree 
were  already  in  existence.  The  former  has  been  found  in  North 
Carolina  and  in  the  Don  River  Valley  in  Ontario.  The  latter  is 
rather  common  throughout  France  as  far  north  as  the  site  of  Paris, 
and  at  a  number  of  locaHties  in  Italy.  Both  the  American  and  the 
European  Judas-trees  frequently  depart  from  the  normal  orbicular 
or  cordate  shape  of  the  leaf,  widening  them  and  developing  an 
emarginate  apex.  This  may  be  an  atavistic  trait,  since  several  of 
the  ancestral  forms  appear  to  have  normally  had  leaves  of  this 
)e. 


J 


CHAPTER  XIX 

Sumach  and  Holly 

The  sumach  and  holly  families  belong  to  the  large  natural  order 
of  plants  called  the  Sapindales  which  includes  a  score  of  families 
and  over  three  thousand  existing  species.  Here  belong  the  box, 
horsechestnuts  and  maples,  as  well  as  hosts  of  unfamiliar  forms  of 
other  climes.  On  the  whole  this  order  does  not  contribute  as  many- 
trees  to  our  temperate  forests  as  it  does  to  those  of  equatorial 
regions. 

THE    SUMACH 

The  sumach,  of  which  there  are  many  kinds,  belongs  to  a  family 
known  botanically  as  the  Anacardiaceae.  This  family  contains  a 
great  variety  of  highly  interesting  plants  such  as  the  oriental  man- 
gos, now  cultivated  in  all  tropical  countries,  and  often  facetiously 
considered  the  basis  of  rebellion  in  the  Antilles  since  the  insurrec- 
tos  could  Hve  entirely  on  mangos  when  they  were  in  season.  It 
includes  also  the  interesting  cashew-nuts,  the  spondias  or  hog-plums, 
pistacia  nuts,  and  many  others  of  the  greatest  importance. 

In  the  modern  world  the  sumach  family  is  divided  into  over  50 
genera  and  nearly  500  species.  All  are  trees  or  shrubs  with  pithy 
branches,  and  a  resinous  milky  juice  that  is  toxic,  alternately 
arranged  simple  or  palmate  or  pinnate  leaves,  and  drupaceous 
fruits.  They  make  their  greatest  display  in  the  tropical  and  sub- 
tropical regions  of  both  hemispheres,  and  are  especially  abundant 
in  the  Malayasian  region. 

The  genus  to  which  the  familiar  sumach  belongs  is  known  as 
Rhus  which  was  the  classical  name  of  the  south  European  sumach. 
Rhus  is  by  far  the  largest  genus  of  the  family,  and  the  only  one  to 
occur  in  the  temperate  regions  of  both  the  Northern  and  Southern 
Hemispheres.  It  contains  over  100  existing  species,  just  about  the 
same  number  as  have  been  found  fossil.     They  are  found  in  all 

206 


SUMACH  AND  HOLLY  207 

temperate  regions  of  the  globe  and  are  perhaps  most  abundantly 
represented  in  South  Africa.  In  North  America  they  are  to  be 
found  from  Canada  to  southern  Mexico,  and  from  the  Atlantic  to 
the  Pacific.  Of  the  17  North  American  forms  5  attain  to  the 
stature  of  small  trees. 

Their  wood  is  too  small  and  has  too  large  a  pith  to  be  of  any 
commercial  value,  although  the  shoots  were  sometimes  used  as 
spouts  in  tapping  the  sugar  maple.  Several  of  the  forms  are 
handsome  ornamental  shrubs  with  beautiful  foUage  and  scarlet 
fruit  clusters.  The  acrid  poisonous  juice  of  the  Chinese  sumach, 
Rhus  vernicifera,  furnishes  the  black  varnish  used  in  China  and 
Japan  in  the  manufacture  of  lacquer.  Other  species  are  sometimes 
used  for  their  contained  tannin  or  for  the  wax  that  is  obtained  from 
their  fruits. 

Our  native  American  forms  show  a  considerable  range  of  varia- 
tions. Some  have  feather-like  leaves,  others  like  the  common 
poison-ivy  have  their  leaflets  in  threes,  and  a  small  Califomian 
tree,  Rhus  integrifoHa,  commonly  known  as  the  mahogany,  fre- 
quently has  simple  holly-like  leaves.  One  shrubby  eastern  form 
is  known  as  the  fragrant  or  sweet  scented  sumach,  and  another 
found  in  our  western  States  is  often  known  as  the  skunk-bush 
because  of  its  vile  odor. 

The  largest  as  well  as  one  of  the  handsomest  sumachs  is  the  stag- 
horn  sumach,  R^ms  hirta,  which  occasionally  reaches  a  height  of 
40  feet.  It  ranges  from  New  Brunswick  to  Minnesota  and  south- 
ward to  Georgia,  Alabama  and  Mississippi  and  is  sometimes  planted 
as  an  ornamental  tree  in  this  country  and  commonly  used  for  that 
purpose  in  central  and  northern  Europe.  It  has  pinnate  leaves, 
10  to  24  inches  long  of  11  to  31  lanceolate  falcate,  toothed  margined 
leaflets,  borne  on  a  velvety  pinkish  stalk,  and  of  a  fine  shade  of 
green  which  becomes  darker  and  more  opaque  with  age.  The 
flowers  are  greenish  and  inconspicuous,  but  the  fruits,  which  are 
in  thick  clusters,  are  bright  crimson  and  very  striking. 

Very  similar  to  the  preceding  but  rarely  over  20  feet  tall  is  the 
upland  or  scarlet  sumach,  Rhus  glabra,  sometimes  called  the  smooth 
sumach  in  contrast  with  the  staghorn  since  it  lacks  the  pubescence 


208  TREE   ANCESTORS 

of  the  latter.  It  is  found  from  Nova  Scotia  to  British  Columbia  and 
southward  to  Arizona  and  Florida.  The  foliage  is  much  like  that 
of  the  staghom,  as  are  its  scarlet  fruits.  It  is  a  hardy  shrub  and 
has  great  possibilities  for  ornamental  plantings  which  seem  to  be 
but  little  appreciated. 

At  least  two  of  our  sumachs  have  an  evil  reputation.  These 
are  the  rather  uncommon  shrub  or  small  tree  of  swampy  situations 
in  our  eastern  States  known  as  the  poison-siunach,  Rhus  veniix. 
It  is  also  sometimes  called  poison-elder,  poison-ash,  or  poison-dog- 
wood, although  the  ash  is  the  only  one  of  these  to  which  it  shows 
any  particular  resemblance.  Its  small  clustered  fruits  are  white, 
and  its  leaves  consist  of  from  7  to  13  smooth  entire  leaflets,  and 
are  very  poisonous  to  most  persons.  Its  restriction  to  out  of  the 
way  swampy  situations  renders  it  less  famihar  than  its  relative 
the  ubiquitous  poison-ivy,  which  almost  everyone  has  become 
acquainted  with  to  their  sorrow,  although  its  poisonous  effects 
vary  greatly  with  the  season  and  with  individuals,  many,  including 
the  writer  being  entirely  immune,  while  others  are  affected  with 
great  severity. 

The  poison-ivy,  or  poison-oak  as  it  is  sometimes  called,  represents 
two  closely  related  botanical  species — Rkus  radicans,  which  ranges 
from  Nova  Scotia  to  British  Columbia  and  southward  to  Florida, 
Arkansas  and  Utah;  and  Rhus  toxicodendron  of  our  southern  States, 
They  are  both  hardy  agressive  woody  vines  of  thickets  or  fence 
rows  or  stone  walls,  occasionally  assuming  an  erect  or  bushy  form. 
They  grow  to  great  lengths,  climbing  by  numerous  aerial  rootlets, 
and  I  have  seen  stems  of  old  plants  in  New  England  that  were  5 
inches  in  diameter.  The  leaves  consist  of  three  leaflets,  which  may 
have  their  margins  entire  or  toothed,  and  which  are  of  a  shiny 
lurid  green  color  The  fruits,  like  those  of  the  poison  sumach,  are 
white,  so  that  if  the  uninitiated  will  avoid  swamp  bushes  or  vines 
with  clusters  of  hard  white  fruits  and  with  trifoliate  or  pinnate 
leaves,  they  mil  save  themselves  any  subsequent  unpleasantness. 

The  last  of  our  American  species  to  be  mentioned  by  name  is  the 
dwarf,  black,  or  mountain  sumach,  Rhus  copallina,  which  is  a  shrub 
or  small  tree  found  from  Maine  and  southern  Ontario  to  Florida 


SUMACH   AND   HOLLY  209 

and  Texas.  It  is  neither  handsome  nor  especially  useful,  and  often 
looks  very  frowsy  because  of  its  susceptibility  to  insect  and  fungous 
infection.  Its  individual  leaves  are  not  unattractive  and  the  plant 
is  interesting  as  an  illustration  of  quiet  and  persistent  aggressiveness. 
Inhabiting  dry  soils,  its  underground  stems  penetrate  for  yards  in 
every  direction,  often  growing  to  considerable  size,  and  sending 
up  new  plants  from  the  nodes.  Many  a  New  England  pasture  has 
been  ruined  by  it,  and  it  cannot  be  eradicated  until  every  vital 
spark  beneath  the  sod  has  been  uprooted.  The  fruit  is  not  hand- 
some, and  the  leaves,  usually  of  entire  leaflets,  pinnately  arranged, 
have  the  stem  margins  winged  between  the  leaflets,  ijiaking  it 
readily  recognizable.  Both  the  leaves  and  the  bark  contain  large 
amounts  of  tannin  and  they  are  sometimes  systematically  collected 
and  used  in  tanning. 

The  geological  history  of  the  sumachs  goes  back  to  the  far  off 
days  of  the  dinosaurs,  and  ten  or  a  dozen  widely  scattered  species 
have  been  found  in  the  rocks  of  the  Upper  Cretaceous  period.  At 
the  beginning  of  Upper  Cretaceous  time  there  was  a  sumach  in 
Saxony,  and  two  in  Kansas  and  Texas,  this  wide  distribution 
showing  that  still  earher  species  await  discovery.  No  sumachs 
have  been  described  from  the  Upper  Cretaceous  of  western  Green- 
land where  so  many  ancestral  trees  have  been  found,  although  it 
is  probable  that  some  of  the  fossil  leaves  found  in  that  region  and 
identified  as  myricas  may  represent  sumachs  instead.  Somev/hat 
later  in  the  Upper  Cretaceous  additional  species  of  sumach  occurred 
in  South  Carohna,  Long  Island,  Wyoming,  Bohemia  and  Italy. 

About  13  forms  are  known  from  the  Eocene.  In  the  earher 
part  of  that  dawning  Tertiary  time  sumachs  occurred  in  Dakota, 
Colorado,  Wyoming  and  Yellowstone  Park.  In  later  Eocene  time 
they  are  known  from  Colorado,  from  central  Europe,  and  in  north- 
ern lands  in  Alaska,  Greenland  and  Iceland.  Four  different  forms 
have  been  found  in  the  upper  Eocene  rocks  of  Greenland,  which  is 
presumptive  evidence  that  they  already  existed  in  that  region  in 
antecedent  Upper  Cretaceous  times. 

The  number  of  species  of  sumach  was  doubled  during  succeeding 
Ohgocene  times.     As  is  the  case  with  so  many  tree  histories,  the 


210  TREE    ANCESTORS 

Oligocene  records  are  all  European,  and  include  France,  Tyrol, 
Italy  and  Prussia,  the  last  found  in  the  celebrated  Baltic  amber 
deposits.  Two-thirds  of  the  known  Oligocene  sumachs  have  been 
found  in  France,  and  the  bulk  of  these  along  with  a  most  interesting 
and  varied  fauna  and  flora,  come  from  the  gypsiferous  clays  of 
southeastern  France.  At  the  time  these  clays  were  being  formed 
and  these  fossil  plants  and  animals  were  living  the  region  was  one 
of  retreating  seas  and  coastal  evaporating  lagoons  in  which  hosts 
of  fishes  perished  and  were  fossilized,  along  with  insects,  and  ter- 
restrial animals  and  plants.  There  is  considerable  of  an  African 
flavor  to  this  life  with  which  the  fossil  sumachs  are  in  accord.  In 
most  of  the  tree  histories  the  reader  will  note  a  falling  off  in  the 
number  of  forms  during  OHgocene  time  due  to  the  climatic  condi- 
tions which  were  rather  warm  and  dry  and  which  were  more  favor- 
able for  plants  of  what  are  now  exotic  types  rather  than  of  the 
familiar  temperate  trees,  but  the  sumachs  are  an  exception  to  this 
general  condition  having  been  particularly  adapted  to  the  climate 
of  the  OHgocene. 

During  succeeding  Miocene  times  the  sumachs  reached  their 
maximum  development  and  probably  were  more  abundant  and  wide- 
spread than  they  are  at  present,  although  only  about  70  Miocene 
species  are  actually  known.  They  were  especially  abundant  about 
the  shores  of  the  Mediterranean  in  the  latter  half  of  the  Miocene. 
Four  of  these  Miocene  sumachs  were  survivors  from  Oligocene 
times.  In  Europe  these  Miocene  sumachs  have  been  recorded 
from  southern  Spain  to  eastern  Greece,  and  they  were  especially 
varied  in  France,  Styria  and  Croatia.  Every  European  region  with 
Miocene  plant  beds  has  its  species  of  sumach.  In  North  America 
Miocene  sumachs  have  been  found  in  Maryland  and  Virginia  on 
the  Atlantic  coast,  and  in  Oregon  and  Cahfomia  on  the  Pacific 
coast.  Seven  different  forms  are  known  from  Cahfomia.  In  the 
interior  they  have  been  found  in  Idaho,  Nevada  and  Colorado.  In 
the  deposits  of  the  celebrated  fossil  lake  at  Florissant  in  the  Colorado 
Rockies,  7  different  sumachs  have  been  found  entombed,  and  this 
vista  furnished  by  the  life  of  this  tiny  lake  basin  suggests  that 
similar  assemblages  must  have  been  present  during  Miocene  times 


SUMACH   AND  HOLLY  211 

in  many  other  basins  in  that  great  mountain  system  where  their 
rehcs  failed  of  preservation  or  have  not  yet  been  discovered. 

Sumach  history  shrinks  greatly  during  the  closing  days  of  the 
Tertiary  period,  the  Pliocene  forms  being  but  5  or  6  in  number, 
and  3  of  these  were  survivors  from  the  Miocene.  The  Pliocene 
records  are  all  European  and  include  species  in  Spain,  France, 
Prussia,  Italy  and  Slavonia.  A  rich  forest  flora  has  been  found  in 
numerous  Pliocene  plant  beds,  especially  in  the  countries  border- 
ing the  PHocene  Mediterranean,  so  that  it  is  difficult  to  think  other- 
wise than  that  this  scarcity  of  the  sumachs  was  real  and  not 
merely  an  apparent  feature  of  PHocene  times.  The  only  Pleisto- 
cene records  of  the  sumach  that  I  know  of  are  3  different  forms  much 
like  still  existing  species  and  found  in  China  and  Japan,  regions 
that  are  still  plentifully  supplied  with  these  plants. 

THE    HOLLY 

"But  when  the  bare  and  wintry  woods  we  see, 
What  then  so  cheerful  as  the  holly-tree." 

— SOUTHEY. 

Holly  inevitably  reminds  us  of  the  hearty  eating  and  deep  drink- 
ing of  the  Anglo-Saxon  Christmas  tide,  with  roaring  yule  logs, 
when  roast  pig  with  a  sprig  of  holly  through  its  heart  had  not  yet 
been  replaced  by  the  turkey,  for  North  America  had  not  yet  been 
discovered.  Like  so  many  of  our  customs,  the  use  of  holly  at 
Christmas  is  of  great  antiquity,  mayhap  a  survival  of  the  practises 
of  the  Roman  Saturnalia,  or  perhaps  not  going  back  farther  than 
the  respectably  ancient  Teutonic  custom  of  using  the  holly  along 
with  other  evergreens  as  a  refuge  for  the  sylvan  spirits  during  the 
inclemency  of  winter. 

When  our  European  ancestors  settled  America  they  found  here 
an  evergreen  holly  practically  indistinguishable  from  their  familiar 
European  tree,  and  its  use  in  wreaths  and  other  Christmas  decora- 
tions has  grown  so  enormously  in  this  country  in  recent  years  as  to 
seriously  threaten  the  continued  existence  of  the  tree.  In  some 
localities  it  is  considered  unlucky  to  bring  the  holly  indoors  before 
Christmas  eve,  and  there  are  many  superstitions  connected  with 


212  TREE   ANCESTORS 

it,  especially  in  the  rural  parts  of  Europe.  Lonicerus  mentions  a 
German  belief  that  consecrated  twigs  of  the  holly  hung  over  a  door 
would  afford  protection  against  Hghtning;  and  holly  used  to  decorate 
churches  in  rural  England  is  deemed  to  bring  good  luck  throughout 
the  year  to  those  fortunate  enough  to  secure  a  sprig,  especially  if 
it  had  berries  on  it. 

The  holly  belongs  to  the  botanical  genus  Ilex,  the  name  being 
the  classical  name  of  the  evergreen  oak  of  southern  Europe  which 
has  leaves  very  much  like  those  of  the  Christmas  holly.  Thus  both 
the  Latin  name  of  the  genus,  and  the  vernacular  name  refer  to  the 
evergreen  holly  of  Europe  which  is  the  only  species  inhabiting  that 
continent  in  the  world  of  today.  However,  there  are  a  great  many 
other  species  of  holly  found  in  different  parts  of  the  world.  Over 
1 70  kinds  have  been  distinguished  by  botanists,  and  some  of  these 
are  found  in  all  tropical  and  temperate  parts  of  the  world  except 
western  North  America,  Australia,  New  Zealand  and  New  Guinea. 

They  are  all  shrubs  or  trees,  with  alternately  arranged,  entire 
or  toothed,  rather  coriaceous  leaves;  small  inconspicuous  flowers; 
and  drupaceous  fruits,  often  bright  colored,  and  enclosing  several 
small  stones.  The  greatest  number  of  these  modern  hollys  are 
found  in  northern  South  America.  The  only  surviving  form  in 
Europe  is  Ilex  aqinfoHum  which  has  dark  green,  shining,  leathery, 
evergreen  leaves,  often  with  spiny  margins,  especially  on  young 
trees.  An  old  border  proverb  defines  a  story  teller  as  one  that 
"lees  never  but  when  the  hoUen  in  green,"  a  most  feHcitous  apella- 
tion  for  a  habitual  Har. 

The  European  tree  is  usually  small  but  is  said  to  reach  a  height 
of  60  to  70  feet  in  Surrey,  and  Loudon  mentions  one  tree  that  was 
80  feet  tall.  It  vnll  grow  on  any  soil  that  is  not  too  wet,  and  is 
common  in  France,  especially  in  Brittany.  There  are  numerous 
varieties  much  used  in  plantings  and  for  hedges,  the  latter  a  practice 
not  followed  in  America.  Evelyn's  holly  hedge  in  Deptford  was 
400  feet  long. 

This  European  tree  is  the  holly  per  se,  or  hulver;  the  aquifoHum 
of  Theophrastus  and  other  classical  writers,  whence  its  modern 
scientific  specific  name.     It  was  the  holen  or  holegn  of  the  Anglo- 


SUMACH   AND   HOLLY  213 

Saxons,  whence  the  term  holm,  applied  to  regions  where  holly 
was  prevalent,  in  which  forms  the  history  of  its  occurrence  is 
preserved  in  many  Teutonic  place  names.  The  wood,  like  that  of 
its  closely  alHed  American  relative,  is  even  grained  and  hard,  almost 
white  in  color,  and  is  used  in  inlaying  and  turning,  and  as  a  substi- 
tute for  ebony  in  handles.  It  was  also  used  to  some  extent  in 
wood  engraving.  The  red  berries  are  greedily  eaten  by  birds 
who  thus  distribute  the  seeds  uninjured,  but  they  induce  violent 
illness  in  man,  which  is  no  hardship  since  they  are  not  at  all 
palatable. 

Our  American  evergreen  holly,  in  every  respect  like  its  European 
cousin,  is  known  as  Ilex  opaca.  It  is  found  naturally  from  the  coast 
of  Massachusetts  southward  near  the  coast  to  peninsular  Florida, 
and  in  the  Mississippi  Valley  from  southern  Indiana  to  the  Gulf  of 
Mexico.  It  is  frequently  cultivated  as  an  ornamental  plant,  as  is 
also  its  European  relative  in  this  country.  It  reaches  a  height  of 
from  40  to  50  feet  with  a  trunk  diameter  of  2  or  3  feet,  and  excep- 
tionally it  may  be  4  feet  in  diameter,  but  large  trees  are  usually 
remote  from  civilization.  Dealers  in  Christmas  greens  have 
seriously  restricted  its  range  in  recent  years  by  destructive  cutting 
and  mutilation.  Doubtless  were  large  trees  accessible  in  any 
quantity  lumbering  would  complete  the  tragedy,  for  the  wood  is 
highly  prized  for  cabinet  work,  turnery  and  interior  finish. 

In  addition  to  the  Christmas  holly  of  our  seaboard  states,  we 
have  a  dozen  other  species  of  holly  in  the  United  States,  collectively 
ranging  from  Nova  Scotia  to  Florida  and  Texas.  About  half  of 
these  have  evergreen  leaves  and  the  others  thinner  and  deciduous 
leaves.  All  are  more  often  shrubs  than  small  trees  and  many  are 
not  even  called  holly  locally,  as,  for  example  the  Ink  or  gall-berry. 
Ilex  glabra,  of  the  eastern  States;  or  the  black-alder  or  fever-bush, 
Ilex  verticillata;  or  the  dahoon.  Ilex  cassine;  or  the  yaupon.  Ilex 
vomitoria. 

The  plants  of  Ilex  contain  a  bitter  principle  known  as  ihcin,  and 
possess  tonic  properties,  and  perhaps  the  most  useful  species  is 
Ilex  paraguariensis  which  furnishes  the  mate  or  Paraguay  tea,  a 
dehghtful  beverage,  the  basis  of  a  very  considerable  industry,  and, 


214  TREE   ANCESTORS 

if  sanguine  advocates  are  to  be  believed,  one  that  is  destined  to 
win  a  world  wide  approval. 

Considerable  is  known  of  the  ancestral  history  of  the  hoUys, 
over  100  different  forms  having  been  discovered  in  the  rocks,  and 
even  this  large  number  is  quite  rightly  considered  to  represent  but 
a  fraction  of  the  hollys  that  have  existed  during  the  past  history  of 
the  earth.  They  appear  first  near  the  base  of  the  Upper  Creta- 
ceous, some  14  different  species  having  been  described  from  the 
rocks  of  that  age.  Half  of  these  Cretaceous  forms  have  been  found 
in  Kansas  in  the  geological  formation  known  as  the  Dakota  sand- 
stone. This  sandstone  represents  the  mantle  of  shore  sands  spread 
by  the  advancing  Cretaceous  sea  that  advanced  from  the  Gulf  of 
Mexico  and  which  eventually  submerged  much  of  the  interior  region 
of  North  America. 

Thus  the  earhest  known  hollys  were  trees  of  sandy  coastal  shores. 
Almost  as  old  as  these  Kansas  hollys  is  a  holly  found  in  what  are 
knowTi  as  the  Atane  beds  of  western  Greenland.  Two  additional 
forms  have  been  found  in  the  later  Cretaceous  of  Greenland,  and 
several  occurred  along  our  Cretaceous  Atlantic  coast  from  Marthas 
Vineyard,  New  Jersey,  Maryland  and  Alabama.  A  single  European 
Upper  Cretaceous  species  has  been  found  in  Bohemia,  and  a  late 
Cretaceous  form  is  recorded  from  Colorado. 

During  Eocene  times  fifteen  different  hollys  were  in  existence. 
A  third  of  these  are  from  rocks  of  early  Eocene  age  in  Dakota, 
Texas,  Louisiana  and  Mississippi,  and  one  is  recorded  from  beds 
of  the  same  age  exposed  on  the  south  coast  of  England.  Later  in 
the  Eocene  several  hollys  occurred  in  Wyoming  and  Oregon;  and 
toward  the  close  of  the  Eocene  five  different  forms  occurred  in 
Greenland  and  one  in  Alaska. 

x\ll  of  the  19  Oligocene  hollys  are  from  European  locaHties. 
They  were  apparently  most  abundant  at  that  time  on  the  Medi- 
terranean coast  of  France  in  the  same  deposits  that  have  furnished 
so  many  sumachs,  but  they  are  also  found  in  Italy,  Germany,  the 
Tyrol,  Bohemia  and  Styria.  Four  of  these  survived  into  the 
succeeding  Miocene  times,  and  very  many  new  forms  made  their 
appearance.     In  all  some  50  different  hollys  are  known  from  the 


SUMACH   AND   HOLLY  215 

rocks  of  Miocene  age.  Miocene  hollys  were  especially  abundant 
in  Europe.  France  alone  had  1 1  different  kinds.  Most  European 
countries  from  Belgium  to  Greece  had  their  Miocene  hollys,  in 
all  about  40  as  compared  with  the  single  existing  European  species. 
In  the  Miocene  of  Asia  the  holly  has  been  found  in  Siberia,  Man- 
churia and  Japan.  In  South  America  it  was  present  in  Colombia 
on  the  north  and  in  southern  Chile  on  the  south.  In  North 
America,  although  there  are  few  Miocene  plant  beds,  hollys  have 
been  discovered  in  Maryland,  Colorado  and  CaHfomia,  In 
the  often  mentioned  lake  beds  at  Florissant  in  the  Colorado  Rock- 
ies, the  remains  of  seven  different  hollys  have  been  found. 

In  the  closing  days  of  the  Tertiary,  or  Pliocene  times,  the  num- 
ber of  species  of  holly  shrank  to  12,  of  which  5  were  survivors  from 
the  Miocene,  but  as  we  know  practically  nothing  of  the  Pliocene 
hollys  that  lived  at  that  time  in  most  of  North  America  and  Asia, 
or  in  tropical  lands,  this  shrinkage  was  probably  more  apparent 
than  real.  PKocene  hollys  are  known  in  Europe  from  Spain,  France, 
Italy  and  Germany.  In  Asia  there  were  two  in  Asia  Minor  and  one 
in  Japan.  In  North  America  2  PUocene  hollys  are  known  and 
both  of  these  were  discovered  in  New  Jersey. 

Following  the  PHocene  came  the  glaciation  of  the  Pleistocene. 
That  its  influence  on  the  forests  was  real  and  not  imaginary  is 
shown  by  the  fact  that  only  a  single  holly  has  survived  in  Europe 
and  this  one  was  already  present  in  the  Pliocene  of  France,  and  it 
occurs  also  in  interglacial  beds  in  north  Germany.  There  was  a 
Pleistocene  holly,  now  extinct,  on  the  island  of  Madeira.  All  of 
the  other  known  Pleistocene  hollys  were  North  American,  although 
this  fact  is  merely  a  reflection  of  the  imperfection  of  the  Pleistocene 
record  and  our  ignorance  of  it  in  most  parts  of  the  world.  These 
American  hollys  include  undetermined  species  found  in  Kentucky: 
the  remains  of  our  Christmas  holly,  Ilex  opaca,  in  the  river  terraces 
of  Maryland,  North  Carolina  and  Alabama:  the  fruits  of  the  ink 
or  gall-berry,  Ilex  glabra,  in  the  celebrated  fossiliferous  deposits 
at  Vero,  Florida,  associated  with  human  and  other  vertebrate 
remains:  the  so-called  black-alder,  Ilex  verticillata,  associated  with 
marine  shells  of  cold  water  marine  animals  in  the  so-called  Leda 
clays  of  Maine:  and  the  leaves  of  the  dahoon.  Ilex  cassine  in  Virginia. 


CHAPTER  XX 

The  Majple 

The  maple  family,  or  Aceraceae  as  it  is  called,  belongs  to  an 
order  of  plants  knowTi  as  the  Sapindales,  which  is  named  from  its 
largest  family,  the  soapberry  family,  a  large  group  of  mostly  tropi- 
cal plants.  In  all  there  are  20  plant  families  grouped  in  this 
order,  containing  over  three  thousand  existing  species.  The  maple 
is  one  of  the  smaller  but  important  families  of  the  order  Sapindales. 
It  comprises  trees,  and  in  a  few  instances  shrubs,  with  well  marked 
characters  of  wood,  leaf,  and  flower,  especially  the  winged  fruits 
or  keys  (technically  samaras)  which  are  familiar  to  all. 

Usually  the  maples  are  segregated  into  3  genera,  although  there 
is  a  great  variation  in  usage  in  this  respect.  These  3  genera  are: 
Dipteronia,  with  a  single  species  in  China;  Negundo,  or  box-elder, 
sometimes  included  with  the  true  maples;  and  Acer,  the  maple, 
with  upwards  of  100  existing  species,  mostly  both  beautiful  and 
useful  widely  distributed  throughout  the  Northern  Hemisphere, 
extending  across  the  equator  to  the  mountains  of  Java,  and  reach- 
ing toward  South  America  in  the  uplands  of  Central  America.  The 
name  Acer  is  the  classical  name  of  the  European  maple. 

It  will  probably  come  as  a  surprise  to  most  of  my  readers  to 
learn  that  maple,  and  particularly  the  sugar  maple,  has  a  strength 
and  stiffness  of  wood  considerably  greater  than  that  of  the  white 
oak,  and  that  this  heavy  tough  narrow  ringed  wood,  which  takes  a 
high  pohsh,  is  one  of  our  most  valuable  timbers.  Lumbermen 
have  been  cutting  it  at  the  rate  of  over  a  billion  board  feet  annually. 
A  large  part  of  this  production  comes  from  the  States  of  Michigan, 
Wisconsin,  Pennsylvania,  New  York  and  West  Virginia,  and  the 
supply  is  being  rapidly  depleted.  Although  available  commercial 
supplies  will  not  last  for  many  years  the  tree  is  in  no  danger  of 
extinction  for  it  is  a  strong  vigorous  agressive  tree,  well  able  to 
hold  its  own  on  fertile  fairly  well  drained  land. 

216 


THE   MAPLE  217 

Although  slow  growing  and  not  often  reaching  its  maximum 
height  of  129  feet  and  trunk  diameter  of  4  feet,  it  producesan 
abundance  of  amply  winged  seeds,  of  which  a  large  number  sprout, 
even  in  the  shade,  and  tend  to  crowd  out  their  elders,  and  when 
once  established  they  successfully  resist  the  encroachment  of  other 
trees.  Few  trees  are  seen  as  frequently  in  woodlots  from  New  Eng- 
land to  Ohio  and  the  Potomac  as  the  sugar  maple. 

In  an  early  volume  of  the  Transactions  of  the  American  Philo- 
sophical Society,  over  a  century  old,  we  read  the  estimate  that  6000 
maple  trees  were  destroyed  in  clearing  the  average  New  York  or 
Pennsylvania  farm.  Rusk,  in  his  letter  to  Thomas  Jefferson, 
just  alluded  to,  suggested  that  at  least  a  third  of  these  trees  should 
not  be  destroyed,  but  should  be  preserved  as  a  source  of  sugar. 
But  who  but  the  few  can  look  forward  a  hundred  years.  The  land 
had  to  be  cleared,  and  much  superfluous  maple  along  with  many 
other  valuable  trees  vanished  up  the  chimneys — maple  back  logs 
were  in  such  demand  that  they  were  once  shipped  regularly  to 
Boston.  Much  maple  went  into  charcoal  for  forging,  and  much 
was  consumed  by  the  makers  of  potash. 

The  strength  and  fine  grain  of  the  wood  caused  it  to  be  valued 
for  rifle  stocks,  saddle  trees,  spinning  wheels  and  reels,  dishes  and 
trenchers.  The  Iroquois  made  paddles  and  spoons  of  it,  and 
Withers,  in  his  Border  Chronicles,  relates  how  in  1777  they  un- 
successfully attempted  to  make  cannon  of  maple  logs.  In  these 
modern  days  maple  is  much  used  for  flooring,  still  more  goes  into 
the  manufacture  of  shoe  lasts,  and  an  even  greater  amount  is 
consumed  by  furniture  manufacturers,  especially  the  pathological 
varieties  known  as  curly,  wavy,  and  birdseye  maple.  Sugar  maple 
stands  first  in  the  list  of  woods  used  in  Illinois  in  the  manufacture 
of  agricultural  implements,  and  it  also  goes  into  wooden  ware,  and 
into  a  thousand  miscellaneous  uses. 

Voorhees  states  that  the  Massachusetts  Indians  taught  the 
Plymouth  colonists  the  value  of  maple  ashes  in  the  raising  of  crops, 
and  the  maple  stands  at  the  head  of  the  list  of  woods  used  for  this 
purpose.  The  colonists  early  exported  ashes,  of  which  those  of  the 
maple  were  considered  the  best  to  England.     Potash  and  pearlash 


218  TREE   ANCESTORS 

are  still  exported  from  Canada,  but  the  amount  is  trifling,  almost 
as  is  the  number  of  households  that  still  hold  to  the  once  universal 
custom  of  making  their  own  soap. 

The  Indians,  from  Canada  to  Dakota  and  southward  to  the 
Carolinas,  made  maple  sugar,  and  the  first  settlers  learned  and 
improved  upon  their  art.  It  is  difficult  to  estimate  the  quantity 
that  is  consumed  locally  or  sold  at  the  present  time,  since  most  of 
it  is  adulterated  by  the  producers,  and  real  maple  sugar  and  syrup 
have  come  to  be  regarded  as  Roman  luxuries  where  formerly  they 
were  little  used  by  anyone  who  could  afi'ord  cane  sugar. 

The  other  species  of  maple  are  less  important  commercially  and 
are  usually  not  reported  by  name  in  statistics,  or  distinguished  by 
lumbermen,  but  they  are  all  similar  in  their  characteristics,  and 
the  foregoing  somewhat  lengthy  enumeration  of  the  utilitarian 
virtues  of  the  sugar  maple  must  suffice  for  our  purpose. 

The  maples  are  widely  distributed  in  North  America,  their 
collective  ranges  extending  from  the  valley  of  the  St.  Lawrence 
southward  to  Florida  and  Texas,  and  westward  to  Alaska  north- 
ward to  latitude  55°,  southward  along  the  Pacific  coast  to  southern 
California,  and  in  the  mountain  States  to  eastern  New  Mexico  and 
Arizona,  and  northern  Mexico.  The  bulk  of  the  American  forms 
are  found  in  the  deciduous  forest  region  of  southeastern  North 
America,  and  similarly,  the  bulk  of  the  more  numerous  Old  World 
species  are  found  in  the  valleys  of  southeastern  Asia. 

]\Iany  of  our  native  species  are  used  as  shade  trees,  for  which 
they  are  admirable,  although  slow  growing.  Several  European 
forms  are  also  widely  planted,  both  in  their  native  lands  and  in 
this  country,  and  several  of  the  smaller,  more  dehcately  lobed  and 
red  leaved  oriental  species  are  much  used  in  ornamental  plantings 
for  parks  and  lawns,  although  none  have  the  handsome  flame  colored 
shades  that  are  common  swamp  maple  displays  in  the  Fall  of  the 
year.  There  are  so  many  maples  that  a  detailed  discussion  of 
their  individual  features  and  occurrences  would  be  tiresome. 

It  is,  however,  very  interesting  to  observe  the  results  of  the 
segregation  caused  by  the  Glacial  period  on  the  Tertiary  circum- 
polar  forests.   Few  maples  were  actually  exterminated  by  the  severi- 


Fig.  43.  Some  Fossil  Maple  Leaves  and  Fruits  (About  i  Natural  Size) 

1.  Acer  caudatum  Heer  from  the  Upper  Cretaceous  of  Greenland. 

2.  Acer  osnionti  Knowlton  from  the  late  Eocene  of  Oregon. 

3.  Acer  Santagatae  Massalongo  from  the  Pliocene  of  Italy. 

4  to  8.  Acer  trilohatum  Al.  Braun  from  the  Tortonian  or  Upper  Miocene  of 
Baden. 

9.  Acer  brachyphyllum  Heer  from  the  late  Eocene  of  Spitzbergcn. 

10.  Acer  jurenaky  Stur  from  the  Sarmatian  or  late  Miocene  of  Hungary. 

11.  Acer  plioca^niciim  Saporta  from  the  Pliocene  of  France.     The  ancestor 
of  the  existing  Acer  polyniorphum  (pahnalum)  of  Europe. 

12.  Acer  narbonncnse  Saporta  from  the  Oligocene  (Chattian)  of  France. 

219 


220  TREE    ANCESTORS 

ties  of  Pleistocene  times  but  their  ranges  were  broken  up  in  an 
astonishing  way.  In  North  America  they  survived  in  our  eastern 
forests,  in  the  Rockies,  and  in  the  Pacific  coastal  region.  Few  were 
left  in  Europe  except  in  the  lands  bordering  the  Mediterranean, 
Many  survived  in  eastern  Asia  and  many  more  have  since  been 
evolved  there,  so  that  at  the  present  time  about  two-thirds  of  the 
existing  maples  find  their  home  in  the  last  named  region.  More- 
over glaciation  resulted  in  the  seeming  pranks  of  distribution 
whereby  our  familiar  eastern  moosewood  or  whistlewood,  Acer 
pennsylvanicmn,  belongs  to  a  section  of  the  genus  whose  ten  other 
species  are  all  confined  to  the  Chinese-Japanese  area.  Similarly 
our  Rocky  Mountain  sugar  maple,  Acer  grandidentatum  belongs 
to  a  section  whose  8  other  species  are  all  Old  World  and  mostly 
Mediterranean:  our  mountain  maple,  Acer  spicatum,  and  broad- 
leafed  maple,  ^cer  wacro/>//j//MW,  belong  to  a  section  whose  score 
of  additional  species  are  all  inhabitants  of  the  Old  World:  the 
Negundos  or  box-elders,  of  which  there  are  3  closely  related  existing 
forms  have  1  in  the  East,  1  on  the  Pacific  coast,  and  the  third  in 
Central  America. 

Even  the  foregoing  brief  statement  should  convince  the  most 
incredulous  that  we  cannot  understand  the  present  day  distribu- 
tion of  any  of  our  trees  without  some  knowledge  of  their  past  his- 
tory, and  when  this  history  approaches  the  completeness  that  we 
hopefully  look  forward  to,  it  will  be  possible  to  explain  much  that 
still  remains  obscure.  We  can  predict  a  priori  that  when  closely 
related  forms  are  remote  from  one  another  today  that  their  ances- 
tors occupied  intermediate  regions,  and  already  the  above  men- 
tioned break  in  the  distribution  of  the  box-elders  is  partially 
bridged  by  Tertiary  forms  in  the  country  between. 

The  geological  history  of  the  ancestral  maples  is  based  upon 
the  fossil  remains  of  the  leaves  and  fruits.  Fortunately  maple 
leaves  have  always  had  a  rather  characteristic  form,  not  exactly 
like  the  leaves  of  any  other  trees,  and  the  earliest  ones  differ  from 
the  modem  ones  in  only  minor  particulars  such  as  having  elongated 
median  lobes  just  as  the  young  leaves  of  seedlings  do  at  the  present 
time.     The  winged  fruits  or  maple   keys  (samaras)  are  also  and 


THE   MAPLE  221 

apparently  always  have  been  characteristic.  The  leaves  are 
superficially  like  those  of  some  of  the  grapes  or  of  the  genus  Cissus 
and  its  allies,  but  are  usually  readily  recognizable,  and  if  the  winged 
fruits  of  the  maple  are  at  all  well  preserved  in  the  rocks  it  is  usually 
not  difiicult  to  distinguish  them  from  the  winged  seeds  of  the 
conifers,  or  from  the  somewhat  similar  winged  fruits  of  certain 
tropical  genera  belonging  to  the  soapberry  and  banisteria  families. 

A  very  large  number  of  fossil  maples  have  been  described,  many 
more  than  are  present  in  the  Hving  flora.  The  oldest  of  these 
come  from  the  Upper  Cretaceous  of  western  Greenland  and  western 
Canada.  Additional  Upper  Cretaceous  species  have  been  recorded 
in  Saxony  and  along  our  middle  Atlantic  coast  but  these  are  not 
certainly  identified. 

At  the  beginning  of  the  Tertiary,  however,  in  Eocene  times, 
maples  were  present  in  force.  Over  a  score  of  different  kinds  have 
been  described  frcm  the  fossil  remains  of  beautifully  preserved 
fruits  as  well  as  the  leaves.  The  maples  had  certainly  reached 
western  Europe  early  in  the  Eocene,  for  a  characteristc  maple 
key  has  been  found  in  the  celebrated  travertine  deposits  of  Sezanne 
east  of  Paris.  In  America  early  Eocene  maples  have  been  found 
in  Yellowstone  Park,  Wyoming,  Colorado,  New  Mexico  and 
Dakota.  In  the  later  Eocene,  coincident  with  the  northward 
spread  of  the  temperate  forests  of  the  globe,  maples  were  abundant 
and  had  penetrated  northward  to  Alaska,  where  3  forms  have 
been  discovered;  to  Greenland  where  5  different  species  have  been 
recorded;  to  Spitzbergen  and  Iceland.  In  beds  of  the  same  age 
3  different  maples  have  been  found  on  the  island  of  Sachalin  north 
of  Japan;  and  in  British  Columbia,  Oregon  and  Wyoming. 

In  the  succeeding  Oligocene  times  the  known  maples  became 
reduced  to  1 1  different  forms,  all  of  which,  like  so  many  other  tree 
types  during  that  time,  are  confined  to  European  locahties.  Six 
of  these  are  from  various  Ohgocene  horizons  in  France,  2  are  from 
Germany,  and  Italy,  Bohemia,  and  Russia  have  each  furnished  a 
single  form. 

The  greatest  display  of  fossil  maples  throughout  the  Northern 
Hemisphere  occurs  in  deposits  which  were  formed  during  the  Mio- 


222  TREE    ANCESTORS 

cene.  Nearly  100  different  kinds  of  leaves  and  fruits  have  been 
described  and  figured  by  paleobotanists,  and  although  it  is  not 
certain  that  all  of  these  numerous  forms  are  true  botanical  species 
and  not  variables  of  a  fewer  number  of  true  species,  the  actual 
number  of  true  species  was  probably  greater  than  exist  in  the 
modem  world. 

Of  these  numerous  forms  1  or  2  are  survivors  from  the  Oligocene 
of  Europe,  and  it  is  in  the  Miocene  deposits  that  the  greatest 
number  have  been  found.  For  example,  in  the  celebrated  Httle 
fossil  lake  at  Oeningen  on  the  Swdss  border  of  Baden,  these  late 
Miocene  lake  beds  have  yielded  14  different  kinds  of  maple  and 
some  of  these  are  exceedingly  abundant  in  the  shales.  The  lake 
waters  must  have  been  filled  with  the  keys  from  the  surrounding 
slopes  when  the  maples  shed  their  fruits  in  the  Spring.  In  the 
similar  Miocene  Rocky  Mountain  lake  at  Florissant,  Colorado, 
where  the  muds  were  exceedingly  fine  grained  and  consisted  largely 
of  volcanic  ashes  from  the  contemporaneous  volcanos  at  Leadville 
and  nearby  locaKties,  6  different  maples  have  been  discovered. 

From  various  horizons  in  the  Miocene  of  France  a  score  of  dif- 
ferent maples  have  been  unearthed,  and  as  many  more  are  recorded 
from  Italian  locaHties.  Evidently  the  country  bordering  the 
expanded  Mediterranean  sea  of  Miocene  time  was  imusually  well 
forested,  and  the  maples  were  a  prominent  element  in  those  forests. 
Other  European  localities  of  Miocene  age  where  maples  have  been 
found  are  Bohemia,  where  they  were  abundant;  Styria;  Switzer- 
land; Croatia;  Germany;  Camiola;  Carinthia;  Transylvania;  Hun- 
gary; Bosnia  and  Greece.  In  Asia  Miocene  maples  have  been 
found  in  Siberia,  in  the  Altai  mountains,  and  in  Japan. 

Athough  apparently  not  as  abundant  in  North  America  at  that 
time,  we  know  much  less  about  the  plant  Kfe  of  this  continent  in 
late  Tertiary  times,  especially  the  Miocene  and  Pliocene  of  the 
central  and  eastern  parts  of  the  continent.  Ten  different  Miocene 
maples  have  been  discovered  in  Oregon  and  the  surface  of  the  Mio- 
cene history  in  that  region  has  scarcely  been  scratched.  Four 
maples  are  known  from  the  Miocene  of  California,  where  also  much 
still  awaits  discovery.  One  is  known  from  Yellowstone  Park,  and 
one  from  British  Columbia. 


THE    MAPLE  223 

The  leaves  and  fruits  of  extinct  kinds  of  maples  are  less  abundant 
in  the  succeeding  deposits  of  Pliocene  age  than  they  are  in  Miocene 
deposits,  but  they  were  still  a  prominent  element  in  the  forests 
of  that  time,  about  forty  different  species  having  been  already 
determined.  Twelve  of  these,  all  Mediterranean  forms  in  Spain, 
France,  Germany,  Austria,  Styria,  Slavonia  and  Asia  Minor,  were 
survivors  from  the  Miocene.  Pliocene  maples  are  most  abundant 
and  varied  in  France,  where  12  different  species  have  been  found. 
Italy  ranks  second  with  10  species.  No  Pliocene  maples  have  been 
discovered  in  North  America,  although  maples  were  undoubtedly 
present  in  both  the  eastern  and  western  parts  of  the  continent  at 
that  time.  In  Asia  Pliocene  maples  have  been  found  in  Indo-China, 
Manchuria  Japan,  and  in  the  Altai  region  of  the  central  part  of 
that  continent.  These  are  mostly  forms  of  Japanese  and  Chinese 
affinities,  where  the  descendants  of  these  late  Tertiary  species  now 
live,  and  several  of  the  fossil  forms  are  undoubtedly  the  direct 
ancestors  of  the  latter. 

A  quite  considerable  variety  of  maples  have  been  found  in  the 
Pleistocene  deposits  of  North  America  and  Europe,  and  as  might 
be  expected,  most  of  these  are  forms  which  still  exist  in  modern 
times.  The  stately  sycamore  maple  of  Europe,  Acer  pseudopla- 
tamis,  was  already  present  in  Phocene  times  in  France  and  in  the 
Pleistocene  it  has  been  found  in  France,  Italy,  Luxembourg  and 
Hungary.  The  existing  Acer  campestre  is  found  in  the  Pleistocene 
of  Germany,  France,  and  Italy.  There  is  a  third  form  in  Germany 
and  2  additional  in  Italy. 

The  records  of  Pleistocene  maples  in  North  America  extend  from 
Ontario  and  Massachusetts  to  Alabama  and  Florida.  The  sugar 
or  rock  maple,  Acer  saccharum,  is  found  fossil  in  southern  Ontario 
and  New  England:  the  silver  or  white  maple,  Acer  saccharinum, 
has  been  found  in  Alabama:  and  the  red  or  swamp  maple,  Acer 
ruhrum,  occurs  in  the  Pleistocene  of  Alabama  and  Florida.  There 
are  still  other,  not  exactly  named  fossil  maples  in  Virginia  and  Mary- 
land, and  a  supposed  extinct  species  has  been  described  from  the 
interglacial  deposits  of  the  Don  valley  near  Toronto,  Canada. 


224  TREE   ANCESTORS 

Several  of  the  fossil  maples  mentioned  in  these  pages  and  repre- 
sented by  both  leaves  and  fruits,  and  from  widely  scattered  regions, 
are  shown  in  reduced  size  on  the  accompanying  plate.  Surely 
botanists  and  tree  lovers  should  not  keep  their  attention  so  closely 
focussed  on  the  woods  and  flowers  of  the  living  world  as  to  lose 
sight  of  the  dead  world  beneath  their  feet,  which  needs  but  under- 
standing to  make  live  again  in  all  its  ages  old  glory  and  impressive- 
ness.  The  Pharoahs  have  long  since  been  mummies.  From  the 
standpoint  of  human  history  the  Chaldeans  and  Assyrians  belong 
to  an  ancient  world,  and  yet  the  maples  along  with  most  of  our 
forest  trees  are  of  a  lineage  so  much  more  ancient  as  to  scarcely  be 
intelligible  or  believable.  Practically  all  of  our  forest  trees  go  back 
farther  than  we  can  trace  the  warm  blooded  animals  that  furnished 
the  stock  out  of  which  humanity  arose  in  the  late  Tertiary,  at 
about  the  time  that  the  most  luxuriant  and  widespread  forests  of 
the  world  were  shrinking  before  those  climatic  changes  that  ushered 
in  the  glacial  period  and  shattered  their  unbroken  and  far  flung 
distribution. 


CHAPTER  XXI 

The  Ash 

"Venus  of  the  woods." 

— Gilpin. 

I  imagine  that  few  of  my  readers  unless  they  be  professional 
botanists  realize  that  our  familiar  ash  of  southeastern  North  Amer- 
ica is  a  member  of  the  olive  family,  or  Oleaceae  as  it  is  known  scien- 
tifically. This  family  of  plants  which  was  named  originally  after 
the  Mediterranean  olive — now  extensively  cultivated  in  Cahfomia — 
contains  a  number  of  other  particularly  well  known  plants  both 
native  and  introduced  from  the  old  world  that  have  long  been 
highly  prized  for  ornamental  planting.  Among  these  the  com- 
monest are  the  Hlac,  privet,  syringa,  forsythia  and  jasmine.  The 
devil-wood  (Osmanthus)  of  our  Gulf  States,  sometimes  called  the 
American  olive,  is  also  a  member  of  this  family. 

The  two  principal  areas  of  distribution  of  the  existing  ashes  are 
southeastern  North  America  and  southeastern  Asia,  although  they 
are  by  no  means  wanting  in  Europe  or  in  the  forested  region  of  our 
Pacific  coast.  There  are  about  the  same  number  of  species  of 
ash  in  China  as  there  are  in  North  America,  but  ours  are  usually 
the  larger  trees  and  furnish  more  valuable  wood.  In  addition  to 
the  ash  there  are  two  other  members  of  the  olive  family  that  are 
common  to  China  and  our  southeastern  states.  These  are  the 
fringe-tree  (Chionanthus)  and  the  devil-wood  (Osmanthus) — 
the  flowers  of  the  latter  being  utihzed  for  scenting  tea  in  China. 

Obviously  the  ash,  fringe-tree,  and  devil-wood  did  not  originate 
simultaneously  or  at  different  times  independently  in  Asia  and 
North  America,  so  that  there  must  have  been  a  time  in  the  past 
when  the  lands  lying  between  these  remote  areas  were  traversed 
by  the  ancestors  of  the  living  forms  that  now  inhabit  them.  On  a 
subsequent  page  we  shall  see  that  this  is  clearly  indicated  in  the 
case  of  the  geological  history  of  the  ash,  and  the  presence  of  a  fossil 

225 


226  TREE    ANCESTORS 

de\'il-wood  (Osmanthus)  in  the  early  Eocene  of  western  Tennessee 
indicates  that  this  genus  also  is  an  ancient  one  that  formerly 
migrated  between  Asia  and  North  America  at  a  time  when  climates 
were  more  suitable  for  such  a  migration  than  they  are  at  the  pres- 
ent time,  a  time  when  a  land  bridge  united  the  two  continents 
across  the  present  Behring  Sea  region. 

The  ashes  have  handsome,  usually  compound  leaves  consisting 
of  a  greater  or  less  number  of  separate  leaflets  arranged  in  a  pinnate 
manner  on  a  central  stipe.  Their  leaves  are  thus  similar  to  those 
of  the  walnuts  and  hickories,  but  may  readily  be  distinguished 
by  their  opposite  arrangement  on  the  branches — the  walnut  and 
hickory  leaves  being  arranged  in  an  alternate  manner. 

The  generic  name  Fraxinus  for  the  ash  genus  is  derived  from 
the  classical  name  of  the  European  ash,  and  the  common  name 
doubtless  refers  to  the  ashy  color  of  its  branches.  Ash  flowers 
are  not  conspicuous  but  the  winged  fruits,  technically  known  as 
samaras,  are  borne  in  panicles  and  are  flmihar  to  all  that  tramp 
the  fall  woods,  each  fruit  resembhng  a  tiny  canoe  paddle. 

Ruskin  with  his  characteristic  unbalanced  enthusiasm  said  that 
there  is  no  lovlier  tree  in  the  world  than  the  common  ash.  Fully 
appreciative  of  the  beauty  of  the  ash  I  must  say  that  I  have  seen 
many  more  lovely  trees.  The  more  practical  Evelyn  says  of  the 
common  ash  of  England:  "In  peace  and  war  it  is  a  wood  in  the 
highest  request."  Toughness  and  strength  go  along  with  elegance 
and  this  is  reflected  in  the  Norse  legend  that  Yggdrasil  (the  ash) 
was  the  tree  which  upheld  the  heavens  and  that  out  of  it  Odin  made 
the  first  man — a  hint  of  the  early  tree  worship  cult  among  the 
Norsemen.  It  is  shown  also  in  the  old  English  custom  of  passing 
children  through  ash  woods  or  through  a  split  ash  tree  as  a  cure 
for  the  rickets. 

The  wood  is  tough,  straight  grained  and  that  of  some  of  the 
species  is  a  most  valuable  timber.  In  Britain  ash  lumber  ranks 
next  to  that  of  the  oak  in  importance.  In  this  country  ash  is  one 
of  the  leading  commercial  hardwoods  and  the  annual  cut  which 
amounts  to  about  $10,000,000  in  value  probably  exceeds  the  annual 
growth  increase  in  the  supply,  so  that  soon  we  will  be  obliged  to 


THE    ASH  227 

bestir  ourselves  and  do  intensive  cultivation  or  see  the  iinportant 
industries  that  use  ash  lumber  pinched  by  scarcity  and  consequent 
higher  prices  or  obliged  to  use  inferior  substitutes. 

Ash  timber  has  such  special  uses  that  it  is  too  valuable  to  be 
used  for  ordinary  construction  purposes.  These  uses  all  depend 
on  its  straightness  of  grain,  elasticity,  strength,  hardness,  and  the 
characteristic  of  wearing  smooth  with  use.  Among  these  special 
uses  the  making  of  handles,  which  the  layman  might  think  unim- 
portant, utilizes  about  22  per  cent  of  the  total  cut  with  a  value  of 
about  $2,000,000  annually.  Next  in  importance  has  been  the  use 
of  ash  for  butter  tub  staves  and  other  dairy  supplies,  which  con- 
sumes over  20  per  cent  of  the  annual  cut.  Vehicle  manufacturers 
take  about  15  per  cent,  while  planing  mills  use  large  amounts  and 
the  manufacturers  of  boat  oars  consume  about  a  quarter  of  a  mil- 
lion dollars  worth  of  ash  lumber  every  year. 

Next  to  spruce,  ash  is  the  most  important  wood  used  in  aeroplane 
construction.  It  enters  into  frames,  outriggers,  skids,  rudders 
and  propellers.  As  recently  as  1914  this  use  amounted  to  a  trifling 
percentage  of  the  total  annual  cut  but  during  the  war  and  at  the 
present  time  this  percentage  must  be  much  larger  although  I  do 
not  have  the  figures.  Ash,  chiefly  black  ash,  enters  largely  into 
bent  frame  parts,  as  well  as  slats  and  splints  for  basketry.  The 
early  settlers  of  New  England  learned  from  the  Indians  of  the 
region  who  had  long  practised  it  the  art  of  making  baskets  of  ash 
splints  and  strips  that  lasted  a  lifetime. 

The  production  of  Chinese  or  insect  white  wax  (Peh-la)  is,  next 
to  agriculture  or  silkworm  culture  (sericulture),  the  most  important 
industry  in  certain  parts  of  China  (Szechuan).  This  wax  is  de- 
posited by  a  scale  insect  of  a  species  of  ash  {Fraxinus  chinensis). 
The  insects  are  bred  on  a  privet  {Ligustrum  lucidum)  another 
member  of  the  family  which  does  not  grow  in  the  immediate  vicinity 
of  the  ash  plantations,  so  that  the  eggs  must  be  carried  rapidly  by 
coohes  a  distance  of  over  150  miles  from  privet  to  ash.  This  Chi- 
nese wax  is  highly  valued  by  the  Chinese  and  since  it  does  not  melt 
until  a  temperature  is  reached  around  180°  it  makes  exceedingly 
valuable  candles,  but  because  of  its  price  it  is  usually  used  merely 


228  TREE    ANCESTORS 

for  the  outer  coating  of  candles.  It  is  also  used  for  coating  pills, 
polishing  jade,  soapstone  and  delicate  furniture,  or  as  a  size  to  give 
a  lustre  to  cloth.  Perhaps  its  most  extensive  use  is  for  glossing 
the  higher  grade  papers  of  native  manufacture. 

A  somewhat  remotely  comparable  product  is  obtained  from  the 
Manna-ash  {Fraxinus  ornus)  of  Mediterranean  Europe.  This 
product  is  the  manna  of  commerce,  and  is  not  a  true  wax,  but  a 
secretion  whose  chief  constituent  is  mannite  or  manna  sugar.  It 
is  obtained  in  commercial  quantities  entirely  from  Sicily,  and  un- 
like the  Chinese  wax  it  is  not  due  to  the  activity  of  scale  insects, 
but  is  obtained  by  making  incisions  in  the  bark.  It  is  thus  not 
related  to  the  manna  of  the  scriptures,  which  last  was  due  to  the 
punctures  of  scale  insects  working  on  Tamarix  trees. 

There  are  upwards  of  50  existing  species  of  ash  and  they  are 
widely  distributed  throughout  the  temperate  regions  of  Eurasia 
and  North  America,  extending  into  the  Tropics  in  both  the  Eastern 
(Java)  and  the  Western  (Cuba)  Hemispheres.  Their  generalized 
hmits  of  distribution  together  with  the  knowTi  fossil  occurrence 
of  the  ash  are  shown  on  the  accompanying  sketch-map.  The 
American  species  number  from  18  to  24  according  to  the  varying 
conceptions  of  different  students  as  to  what  constitutes  a  species. 
Three  of  these  {Fraxinus  breggii,  F.  cuspidata  and  F.  dipetala) 
are  shrubby  forms  of  the  southwest.  The  three  important  com- 
mercial species  are  the  white  ash  {Fraxinus  americana),  the  green 
ash  {Fraxinus  lanceolata)  and  the  black  ash  {Fraxinus  nigra). 
The  lumber  trade,  however,  may  only  recognize  white  or  dark  ash, 
or  more  often  simply  ash,  and  all  or  some  of  the  other  species 
that  are  cut  go  to  swell  these  categories. 

The  white  ashes,  which  include  the  species  F.  americana,  F. 
texensis  and  F.  biltvwreana  are  upland  forms.  The  green  ashes, 
which  include  a  large  nimiber  of  less  important  species  than  the 
important  Fraxinus  lanceolata  (namely  F.  darlingtonii,  F.  mi- 
chauxii,  F.  profunda,  F.  berlandieriana,  F.  pennsylvanica,  F.  oregona^ 
F.  velutina,F.  toumeyi,  and  F.  coriacea),Sire  broadly  speaking  bottom 
land  dwellers.  The  water  ashes,  Fraxinus  caroliniana  and  F. 
pauciflora  are  swamp  trees:  while  the  black  ashes,  Fraxinus  quad- 


THE    ASH  229 

rangulata,  F.  anomala  and  F.  nigra  are  trees  of  what  might  be 
called  unfavorable  situations  such  as  dry  hills  and  cold  swamps. 
The  shrubby  species  are  chaparral  and  upland  forms  of  the  arid 
southwest. 

The  geographical  extent  of  the  different  existing  species  seems 
to  be  determined  very  largely  by  the  lightness  and  durability  of 
the  seeds  and  their  quickness  of  germination  combined  with  the 
frequency  of  seed  years,  that  is  to  say  the  factors  are  largely  those 
of  seed  dispersal.  In  accordance  wdth  this  dictum  it  has  been 
found  that  the  so-called  green  ashes  are  the  most  aggressive  and 
\^ddely  distributed ;  Lhe  white  ashes  are  but  Httle  less  so ;  while  the 
water  ashes  and  the  black  ashes  seem  to  be  the  least  fitted  for  main- 
taining their  present  range. 

Not  all  of  the  trees  called  by  the  name  of  ash  are  related  to  the 
true  ashes — thus  the  poison-ash  of  our  eastern  States  is  a  species 
of  sumach  (Rhus) ;  the  bitter  ash  of  the  West  Indies  is  a  species 
of  Simaruba;  the  Cape  Ash  of  South  Africa  is  a  species  of  Eke- 
bergia;  the  prickly  ash  of  our  eastern  States  is  a  Xanthoxylon; 
and  the  familiarly  cultivated  rowan  or  mountain-ash  of  America 
and  Europe  are  related  species  of  the  genus  Sorbus  and  belong  to 
the  rose  family  (Rosaceae),  in  fact  none  of  these  that  I  have  enum- 
erated belong  to  the  same  family  as  the  true  ash. 

The  earliest  known  fossils  that  have  been  referred  to  the  ash 
are  leaves,  whose  identity  is  not  conclusive,  from  what  have  been 
called  the  Patoot  beds  in  western  Greenland.  These  deposits  are 
of  late  Upper  Cretaceous  age  and  are  underlain  in  that  region  by 
the  older  deposits  known  as  the  Atane  beds  which  also  contain 
numerous  plants  including  walnuts,  magnolias,  persimmons,  pop- 
lars, and  other  species  of  ancestral  trees,  but  no  traces  of  the  ash. 
The  correctness  of  the  identification  of  these  Patoot  species  of  ash 
is  really  one  of  shght  importance  for  the  deposits  in  which  they  are 
found  are  immediately  overlain  by  a  series  of  Hgnitic  shales  and 
basalts  of  early  Tertiary  age  and  an  abundant  fossil  flora  has  been 
found  in  these  shales  including  undoubted  remains  of  the  ash.  We 
know  this  since  these  same  sort  of  leaves  are  found  in  the  Eocene 
of  the  United   States  associated   with   characteristic  ash  fruits. 


230  TREE    ANCESTORS 

The  history  of  the  ash  is  hence  known  to  go  back  at  least  as  far 
as  the  dawn  of  the  Tertiary  period,  an  interval  of  several  milHon 
years,  to  a  time  antedating  the  five  toed  ancestral  horses,  or  for 
that  matter  any  of  the  lines  leading  to  the  higher  mammalia. 

About  a  dozen  Eocene  species  of  ash  are  known.  They  are 
found  from  Greenland  to  Louisiana,  and  from  Alaska  to  Oregon, 
Colorado  and  Wyoming.  Their  remains  include  leaves  and  char- 
acteristic fruits  or  ash-paddles.  Eocene  species  of  both  of  which  are 
much  like  their  modern  relatives.  All  of  these  Eocene  forms 
that  have  thus  far  been  discovered  are  either  North  American  or 
Arctic  American — none  having  as  yet  been  found  in  the  abundant 
Eocene  floras  of  Europe,  and  Asia  being  practically  unknown. 
Undoubtedly  there  were  Eocene  ashes  in  northeastern  Asia  for  we 
find  there  many  of  the  forms  found  at  that  time  on  this  side  of 
Behring  strait  in  Alaska.  We  may  tentatively  assume  that  the 
ash  originated  at  some  time  during  the  late  Cretaceous  on  the  North 
American  mainland  or  in  the  region  north  of  it.  Very  little  is  known 
of  the  geologic  history  of  plants  in  the  vast  region  of  Asia,  as  already 
remarked,  but  if  the  ash  had  originated  on  the  latter  continent  it 
should  have  spread  to  Europe,  where  Eocene  plant  beds  are  so 
common,  about  as  quickly  as  it  cHd  to  North  America.  This  fact 
and  the  large  number  of  American  Eocene  species  fortify  the 
conclusion  that  the  early  ash  was  an  American  product. 

However,  the  ash  was  well  on  its  way  toward  Europe  for  during 
the  succeeding  Oligocene  the  leaves  and  fruits  are  found  at  a 
large  number  of  localities  on  that  continent,  from  the  amber 
beds  on  the  shores  of  the  Baltic  to  the  gypsum  beds  along  the 
shores  of  the  Gulf  of  Lyons.  Ten  dift'erent  forms  of  Oligocene 
ash  are  known  and  these  are  all  European,  since  Asia  remains 
unknown  and  in  North  America  the  deposits  of  Oligocene  age  are 
largely  marine  marls  or  limestones  along  the  continental  borders 
or  flood  plain  and  channel  deposits  in  the  interior  in  Vv^hich  fossil 
plants  seem  to  be  rarely  found.  Tv/o  fruits  of  Oligocene  ashes 
from  Europe  are  shown  on  the  accompanying  plate. 

Passing  to  Miocene  times,  which  succeeded  those  of  the  Oligo- 
cene, we  find  Fraxinus,  like  most  of  the  other  tree  genera,  to  have 


THE   ASH  231 

been  widespread,  diversified  and  common,  and  probably  more 
abundant  than  at  the  present  time— their  geograpliical  range  was 
certainly  more  extensive  then  than  now.  Over  30  different  ashes 
are  known  from  Miocene  deposits.  They  are  found  in  North 
America  in  Oregon  on  the  west  coast  and  in  Virginia  on  the  east 
coast.  A  hint  at  their  probable  abundance  at  this  time  in  the 
Rocky  Mountain  region  is  given  to  us  by  the  lake  deposits  at 
Florissant,  Colorado,  where  the  fortunate  preservation  of  the 
sediments  of  this  tiny  lake  basin  furnish  an  unparalleled  picture 
of  the  insect  and  plant  life  of  Miocene  times  in  that  region. 

No  less  than  seven  species  of  ash  have  been  discovered  in  these 
Florissant  beds,  thus  indicating  that  the  ash  was  much  more 
abundant  and  diversified  at  that  time  than  would  otherwise  have 
been  suspected  from  a  consideration  of  the  rather  infrequent  Mio- 
cene plant  beds  of  other  parts  of  North  America.  Fraxinus  is 
present  in  all  of  the  more  important  Miocene  plant  bearing  deposits 
throughout  Europe,  and  it  appears  to  have  been  especially  abun- 
dant in  late  Miocene  times  along  the  shores  of  the  Mediterranean 
and  in  the  uplands  of  central  France,  southern  Germany,  and  in 
the  various  crown-lands  of  the  Austrian  monarchy.  An  ash  leaf 
from  the  Miocene  of  Virginia  is  much  like  that  of  our  modern 
species. 

Ashes  seem  to  have  declined  in  variety  during  the  succeeding 
Pliocene  times,  and  the  few  species  that  have  been  discovered  all 
show  a  near  approach  in  their  characters  to  those  of  the  existing 
species.  Thus  in  Spain,  France  and  Italy  fossil  leaves  are  found 
in  the  Pliocene  deposits  that  are  indistinguishable  from  those 
of  the  existing  Manna-ash  {Fraxinus  ornus)  of  southern  Europe, 
whose  range  at  that  time  Kke  that  of  the  so-called  Hipparion  fauna, 
was  much  greater  than  at  present,  for  its  leaves  have  been  found 
in  the  PHocene  deposits  of  the  Altai  mountains  of  central  Asia. 
Similarly  modern  looking  ash  leaves  are  found  in  the  Pliocene 
deposits  along  our  Gulf  coast  in  what  has  been  called  the  Citronelle 
formation. 

During  the  succeeding  Pleistocene  times,  marked  by  continental 
ice  sheets,  the  ashes  that  have  been  found  fossil  are  all  still  existing 


232  TREE   ANCESTORS 

species,  and  include  at  least  two  European  and  two  American 
forms.  These  all  occur  either  far  to  the  southward  of  the  ice 
sheets,  as  for  example  Fraxinus  ornus  in  Italy,  or  in  Interglacial 
deposits,  as  for  example  Fraxinus  excelsior  in  France  and  Germany. 
In  this  country  our  white  ash,  Fraxinus  americana,  is  found  in 
the  early  Pleistocene  of  western  Kentucky  and  the  late  Pleistocene 
of  Maryland;  the  existing  blue  ash  {Fraxinus  quadrangulata)  of 
the  Mississippi  valley  was  present  and  pushed  northward  as  far 
as  the  Don  Valley  in  Canada  during  an  Interglacial  period  when 
the  climate  for  a  time  was  somewhat  warmer  than  it  is  at  the 
present  time  in  the  same  latitude. 


CHAPTER  XXII 

The  Linden  or  Basswood 

"A  summer  home  of  murmurous  wings, 
And  all  around  the  large  lime  feathers  low." 

— Tennyson. 

The  family  Tiliaceae  to  which  the  Linden  belongs  comprises 
about  35  genera  and  upwards  of  400  existing  species.  These  are 
chiefly  tropical,  and  they  are  massed  in  two  general  regions — one 
around  the  Indian  Ocean  and  the  other  in  northern  South  America. 
The  number  of  genera  that  have  known  fossil  representatives  is 
tmfortimately  limited  to  ancestral  forms  of  the  linden  (Tilia),  to 
the  genus  Grewiopsis  which  is  ancestral  to  the  existing  oriental 
species  of  Grewia,  and  to  the  genus  Triumfetta  which  is  found  in 
the  tropics  of  both  hemispheres  and  abundant  in  the  Antilles  and 
tropical  South  America,  with  two  fossil  species  in  the  lower  Miocene 
of  Chile:  To  Apeihopsis  which  is  ancestral  to  the  South  American 
genus  Apeiba,  and  to  the  South  American  genus  Luhea.  All  of 
these  indicate  that  in  former  times  the  geographical  distribution 
of  the  various  members  of  this  family  was  very  different  from  what 
it  is  at  the  present  time. 

The  genus  Tilia,  which  gives  its  name  to  the  family,  although 
belonging  to  a  family  that  is  essentially  tropical,  is  itself  confined 
to  the  North  Temperate  Zone,  occurring  on  all  of  the  great  northern 
land  masses,  but  now  absent  in  western  North  America,  in  central 
Asia,  and  in  the  Himalayan  region.  All  of  the  existing  species 
are  trees,  all  have  similar  simple  alternate  leaves  with  free  stipules, 
all  have  similar  flower  clusters  borne  on  a  large  leaf-like  bract,  and 
the  fruits  are  nut-like,  although  some  of  the  members  of  the  family 
have  capsular  fruits. 

The  wood  is  pale  in  color  and  soft,  but  straight  grained  and 
easily  worked.  In  America  it  is  commonly  known  as  whitewood,  a 
name  which  it  shares  with  the  wood  of  the  tuhp-tree,  Liriodendron, 

233 


234  TREE    ANCESTORS 

although  the  terms  basswood  and  linn  are  also  frequently  applied 
to  it.  Pulp  mills  consume  large  amounts  of  timber  annually  and 
the  lumber  enters  very  largely  into  interior  finish  and  planing 
mill  products,  cheap  furniture,  turnery  and  similar  uses. 

There  are  about  a  score  of  existing  species,  about  equally  divided 
between  North  America,  Europe  and  Asia.  Apparently  all  of 
these  have  very  fragrant  flowers,  rich  in  nectar,  and  thus  the  source 
of  large  quantities  of  honey — the  Hght  colored  honey  known  as 
bass-wood  honey  in  our  northeastern  states.  This  utility,  es- 
pecially in  the  earher  days  of  the  human  race,  has  made  the  linden 
a  favorite  tree,  and  we  find  it  mentioned  by  Theophrastus,  Pliny, 
Virgil,  Aristophanes  and  other  early  writers.  The  Romans  knew  it 
as  Tilia  and  Virgil  speaks  of  it  particularly  and  mentions  the  quality 
of  the  yokes  made  from  its  wood.  Americans  know  it  best  as 
basswood  (bastwood).  Lime  is  the  favorite  name  in  England, 
doubtless  a  modification  of  the  old  English  lind.  In  our  South  it 
is  often  called  Knn.  Linden  is  the  favorite  of  the  Germans  and  it 
is  much  mentioned  in  their  folk  poetry  and  early  romances.  The 
word  occurs  in  Beowulf,  and  it  was  a  leaf  settling  between  his  shoul- 
ders as  he  bathed  beneath  the  Unden  that  enabled  Hagen  to  stab 
the  otherwise  invulnerable  Siegfried. 

Aside  from  the  compact  handsome  form  of  the  tree  and  the  beauty 
of  its  foliage,  I  suspect  that  its  association  with  bee  keeping  and  the 
distillation  of  the  oil  from  its  flowers  for  use  in  perfumery,  has  some- 
thing to  do  with  widespread  custom  of  planting  both  the  American 
and  the  European  form  as  shade  trees,  even  though  most  of 
humanity  is  no  longer  fortunate  enough  to  keep  bees,  and  as  a 
shade  tree  the  linden  is  not  very  large  and  somewhat  untidy. 

The  various  species  of  linden  in  the  United  States  go  by  the 
names  of  linden  or  basswood,  less  frequently  the  tree  is  termed 
bee-tree  or  linn,  the  last  name  being  common  in  certain  southern 
States,  both  the  last  two  being  essentially  rural  and  the  first  two 
more  especially  urban.  Very  infrequently  are  these  trees  called 
Hmes  in  this  country  although  the  latter  name  is  perhaps  the 
one  most  commonly  applied  to  them  in  Europe  as  a  whole, 
where,   as  previously   mentioned,  it  is  probably  derived  as  an 


THE    LINDEN   OR   BASSWOOD  235 

altered  form  of  the  old  English  lind.  The  tree  was  introduced 
into  England  (Kent),  some  say  by  the  Romans,  which  is  not 
improbable.  Others  place  the  date  of  its  introduction  as 
late  as  1590. 

Some  individual  trees  grow  to  a  great  size  and  corresponding  old 
age.  Ray  mentions  a  European  linden  that  was  48  feet  in  cir- 
cumference, although  this  seems  unusually  large.  The  famous 
linden  that  gave  the  town  of  Neuenstadt  in  Wiirttemberg  the 
appellation  of  "Neuenstadt  an  der  grossen  Linden,"  was  9  feet 
in  diameter.  There  is  a  record,  how  accurate  it  is  hard  to  say,, 
made  in  1798  of  a  linden  at  Trous  which  was  51  feet  in  circumfer- 
ence, and  which  was  said  to  have  been  already  a  celebrated  tree, 
in  1424.     Its  age  was  estimated  at  580  years. 

Many  of  our  American  streets  are  lined  with  lindens,  more  often 
the  European  than  our  native  form,  and  most  of  our  larger  eastern 
cities  have  a  Linden  Avenue.  Perhaps  the  two  most  famous  ave- 
nues of  hndens,  however,  are  those  at  Trinity  College,  at  Cambridge 
in  old  England,  and  "Unter  den  Linden"  in  Berlin.  In  the  regions 
more  remote  from  the  work-a-day  world  where  wood  carving  is 
not  a  lost  art,  linden  wood  is  very  largely  used  for  this  handicraft,, 
and  in  backward  countries  like  much  of  Russia,  the  bast  or  inner 
bark  of  the  linden  is  used  in  the  manufacture  of  cords,  fish  nets  and 
similar  articles.  Bast  mats  made  of  this  material  are,  or  were 
before  Russia  emerged  from  the  necessity  of  working,  a  regular 
article  of  commerce  and  largely  exported.  The  American  Indian 
independently  discovered  this  use  for  the  inner  bark  or  bast  of  our 
species,  and  also  utilized  the  easily  worked  wood  for  the  making 
of  utensils,  Longfellow  narrating  that  all  of  the  bowls  at  Hiawathas 
wedding  being  of  basswood,  smoothly  polished. 

The  somewhat  generalized  range  of  the  existing  species  and  the 
known  fossil  occurrences  of  the  hndens  are  shown  on  the  accompany- 
ing sketch-map  of  the  world.  The  number  of  fossil  species  is 
inconsiderable,  comprising  not  more  than  30  known  forms,  which 
is  really  a  small  number  when  one  reflects  on  the  countless  cen- 
turies that  these  trees  have  been  represented  in  the  forests  of  past 
geological  times,  and  the  vast  areas  that  they  have  ranged  over 


236  TREE    ANCESTORS 

during  those  ages.  As  far  as  is  known  at  the  present  time  no 
Hndens  have  been  found  in  deposits  as  old  as  the  Upper  Cretaceous, 
and  the  hnden  hne  is  therefore  less  ancient  than  that  of  the  majority 
of  our  forest  trees,  unless  possibly  the  unknown  expanse  of  Asia 
has  Cretaceous  lindens  hidden  somewhere  in  its  bosom. 

The  oldest  known  lindens  are  found  in  the  Eocene  or  early  Ter- 
tiary. In  the  rocks  of  this  age  4  or  5  different  species  have  been 
discovered  and  although  this  number  is  small  the  localities  where 
they  have  been  discovered  point  rather  unmistakably  to  the  region 
where  the  linden  stock  originated.  None  occur  south  of  latitude 
40°  and  two  come  from  north  of  latitude  60°,  one  of  the  latter  being 
found  as  far  north  as  Spitzbergen.  A  linden  was  recorded  by 
Heer  from  the  upper  Eocene  of  Grinnell  Land  within  10°  of  the  North 
pole,  but  it  seems  rather  to  represent  a  hazel  (Corylus).  This 
species,  in  part  apparently  representing  a  linden  is  known  as  Tilia 
Mahngrcni  and  a  leaf  of  this  far  northern  form  is  shown  on  the 
accompanying  plate.  It  had  typical  broad  leaves  about  the  size 
of  those  of  the  existing  European  lime.  It  has  been  recorded  from 
rocks  which  are  probably  late  Eocene  in  age  in  both  Spitzbergen 
and  Iceland,  where  it  is  associated  with  volcanic  rocks  (basalts) 
that  seem  to  have  characterized  the  earlier  Tertiary  throughout  the 
North  Temperate  and  the  Arctic  regions.  It  affords  perhaps  the 
most  striking  illustration  of  the  different  climate  and  floral  dis- 
tribution that  is  disclosed  by  a  review  of  the  ancestors  of  any  of 
our  trees,  and  it  is  almost  impossible  for  us  to  picture  forests  of 
broad  leaved  temperate  trees  covering  the  present  perpetually  ice 
clad  wastes  of  the  far  North,  and  flourishing  where  the  winter's 
night  lasted  for  six  months. 

A  second  Eocene  species  occurs  in  the  Kenai  region  of  Alaska 
and  a  third  on  Sachalin  Island  off  the  Asiatic  coast  immediately 
north  of  Japan.  A  fourth  has  been  found  in  the  early  Eocene  of 
Montana.  This  Eocene  distribution  would  seem  to  indicate  that 
the  linden  stock  originated  somewhere  in  the  far  north,  but  whether 
actually  in  the  Polar  region  or  in  northern  North  America  or  north- 
ern Asia  it  is  impossible  to  say.  The  Montana  species  is  some- 
what older  than  the  other  known  Eocene  forms  and  this  may  mean 


THE   LINDEN   OR   BASSWOOD  237 

that  it  is  nearer  than  the  others  to  the  place  of  origin  of  the  genus, 
or  it  may  be  clue  simply  to  accidents  of  preservation  or  of  dis- 
covery since  earher  forms  in  other  areas  may  not  have  been  pre- 
served at  all  or  may  still  be  awaiting  discovery  in  the  rocks. 

No  Oligocene  lindens  are  known  and  this  must  be  ascribed  to 
the  reasons  mentioned  at  the  close  of  the  preceding  paragraph  since 
in  the  succeeding  Miocene  times  there  was  a  great  display  of  a 
varity  of  lindens.  They  are  found  at  this  time  from  the  base  to  the 
top  of  the  Miocene  deposits  of  Europe,  where  plant  beds  of  this 
age  are  much  more  abundant  than  they  are  in  either  North  America 
or  Asia.  At  least  fourteen  different  Miocene  species  are  known 
and  their  remains  include  several  of  the  characteristic  and  curiously 
bracteate  fruits  which,  when  ripe,  turn  brown  and  serve  the  vol- 
planing habit  by  which  the  distribution  of  the  seeds  is  effected, 
as  well  as  a  variety  of  leaves. 

The  lindens  are  especially  abundant  and  varied  in  the  late  Mio- 
cene of  southern  Europe  along  the  shores  of  the  expanding  Mediter- 
ranean sea  of  that  time,  and  in  the  Pyrenees,  the  foothills  of  the 
Apennines  and  in  the  mountains  of  Transylvania,  Styria  and  Bo- 
hemia. The  fruit  of  one  of  these  late  Miocene  species  found  near 
Vienna  in  Austria  and  named  Tilia  vindohonensis  from  the  old 
Roman  name  of  Vienna  is  shown  on  the  accompanying  plate. 

The  Miocene  records  in  North  America  are  scanty  but  the  genus 
was  still  represented  in  the  Rocky  Mountain  region  having  been 
found  in  deposits  of  this  age  in  the  Yellowstone  Park  and  in  the 
lake  basin  at  Florissant,  Colorado,  both  of  which  localities  are 
now  separated  by  several  hundreds  of  miles  of  treeless  plains 
country  from  the  westernmost  outposts  of  the  existing  species  in 
the  river  valleys  of  eastern  Kansas  and  Nebraska. 

The  known  Pliocene  hndens,  owing  to  the  rarity  of  plant  beds 
of  this  age  in  North  America,  are  confined  to  Eurasia,  although 
the  genus  was  undoubtedly  present  in  North  America  during  the 
Pliocene  since  it  is  found  in  the  deposits  of  the  immediately  pre- 
ceding and  succeeding  times.  There  are  four  PHocene  forms 
recorded  from  Europe  where  they  are  found  in  variety  and  abund- 
ance in  the  Auvergne  region  of  France,  and  in  northern  Italy.     In 


238  TREE    ANCESTORS 

Asia  the  existing  Japanese  "ash,"  Tilia  cordata,  a  typical  linden, 
has  been  discovered  in  the  Pliocene  deposits  of  the  Buchtorma  Valley 
in  the  Altai  region  of  the  central  part  of  that  continent  and  is  also 
probably  the  tree  upon  which  the  paleobotanist  Nathorst  bestowed 
the  name  of  Tilia  distans  for  specimens  found  in  the  late  Tertiary 
at  Mogi,  Japan.  Another  linden  fossil  found  at  Mogi  and  not 
given  a  distinctive  specific  name  is  ancestral  to  the  existing  Tilia 
mandschurica  now  found  on  Nippon,  and  in  Manchuria  and  the 
lower  Amur  region. 

Although  the  Pleistocene  records  of  the  Hnden  are  not  numerous 
nevertheless  lindens  are  found  in  deposits  of  this  age  in  both  North 
America  and  Europe.  Fruits  of  two  different  forms  occur  in 
Interglacial  beds  in  Germany  and  Tilia  wood  is  recorded  from  the 
lower  Pleistocene  of  Holland.  The  leaves  of  the  still  existing  bass- 
wood,  which  is  the  most  widely  ranging  of  our  American  lindens  have 
been  found  in  the  Interglacial  beds  of  the  Don  Valley  near  Toronto, 
and  another  form,  or  perhaps  the  same  species  under  another  name 
is  found  in  the  late  Pleistocene  terrace  deposits  of  the  Delaware 
River  in  southern  New  Jersey.  Undoubtedly  other  of  the  existing 
species  were  already  in  existence  and  it  would  not  be  at  all  sur- 
prising if  the  southern  basswood  were  discovered  in  the  similar 
river  terraces  of  our  southern  States. 


CHAPTER  XXIII 

The  Dogwood  and  Gun 

The  Cornel  family,  which  is  the  vernacular  name  of  the  family 
to  which  the  dogwood  and  gum  belongs — the  Comaceae,  as  it  is 
known  scientifically,  contains  about  15  genera  and  a  great  many 
species  or  different  kinds  of  shrubs  and  trees,  widely  distributed 
throughout  the  modem  world  and  mostly  unknown  to  all  except 
the  professional  botanist. 

THE   DOGWOOD 

The  dogwoods,  known  scientifically  as  Cornus,  derived  from  the 
Latin  cornu,  a  horn,  in  allusion  to  the  hardness  of  the  wood,  em- 
brace 40  to  50  existing  kinds  of  shrubs  and  small,  economically 
unimportant  hardwood  trees.  These  are  widely  distributed 
throughout  the  three  continents  of  the  Northern  Hemisphere,  and 
cross  the  equator  into  South  America.  Here  in  North  America 
we  have  17  or  18  species,  of  which  4  attain  to  the  stature  of  trees, 
and  it  depends  whether  you  Hve  on  the  Atlantic  or  Pacific  coasts 
as  to  what  the  name  dogwood  calls  to  mind. 

The  dogwoods  are  chiefly  moisture-loving  plants,  growing  either 
in  naturally  moist  soils,  or  in  forests  where  shade  and  ground 
litter  conserve  the  soil  water.  The  often  bright  colored  and  some- 
times exceedingly  handsome  fruits  are  eagerly  eaten  by  birds  and 
mammals  with  no  injury  to  their  contained  seeds  wliich  are  thus 
widely  distributed.  The  flowers  themselves  are  small,  crowded 
together  and  inconspicuous,  but  are  surroimded  by  from  four  to 
six  large  wliitish  or  pinkish  bracts  that  constitute  the  "flower" 
to  the  average  person,  and  it  is  these  showy  bracts  to  which  the 
beauty  of  the  dogwood  blossoms  are  due.  Next  spring  when  the 
dogwood  wliitens  the  woods  and  you  bring  some  sprays  indoors 
examine  them  carefully  and  you  will  see  the  small  yellowish  true 
flowers  forming  the  central  disk  with  the  pinkish  leaves  or  bracts 

239 


240  TREE    ANCESTORS 

surrounding  them.  The  latter,  in  our  eastern  species,  show  the 
harder  brownish  apical  notches  that  preserve  the  shape  they  had 
when  they  were  merely  leaves  or  scales  protecting  the  bud  before 
they  grew  out  to  form  the  showy  bracts. 

In  the  eastern  United  States  the  name  dogwood  refers  primarily 
to  the  so-called  flowering  dogwood  as  contrasting  it  with  some  of 
the  less  conspicuous  forms  that  lack  the  showy  bracts.  Its  scientific 
name  is  Cornus  florida,  and  it  is  commonly  a  small  tree  with  slender 
spreading  or  upright  branches,  the  flower  heads  with  large  bracts 
which  are  generally  white  but  often  pink  or  reddish,  and  notched 
at  their  tips.  The  fruits  are  in  clusters,  bright  scarlet  in  color, 
and  very  beautiful. 

The  dogwood  is  usually  an  under  tree  of  the  forest  and  it  is  found 
from  Massachusetts  to  Ontario,  and  eastern  Kansas  and  southward 
to  central  Florida  and  Texas,  reappearing  on  the  uplands  of  northern 
Mexico  where  it  was  apparently  left  during  the  Pleistocene,  or  time 
immediately  preceding  the  present,  by  the  development  of  the  arid 
country  along  the  international  boundary.  The  wood  is  close 
grained  and  heavy  and  much  used  for  turnery,  bearings,  handles, 
and  occasionally  for  engravers'  blocks.  It  is  never  abundant  enough 
to  be  classed  as  lumber. 

The  dogwood  is  frequently  planted  in  parks  and  on  private 
lawns  in  our  eastern  States,  and  forms  a  most  attractive  mass  of 
color  in  both  the  vernal  and  autumnal  seasons.  Nothing  is  more 
beautiful  than  the  rich  woods  of  the  Middle  and  South  Atlantic 
States  with  dogwood  interspersed  with  the  leafless  but  brilKant 
red-bud  or  Judas-tree  (Cercis).  Two  of  our  other  native  dogwoods 
which  reach  the  stature  of  trees  have  inconspicuous  blossoms  and 
are  little  known.  The  fourth  and  only  other  showy  species  is  the 
western  dogwood,  Cornus  nuUalli.  Like  its  eastern  relative  it 
flowers  in  the  spring  of  the  year,  its  button-like  cluster  of  small 
greenish  yellow  flowers  being  surrounded  by  from  four  to  six 
showy  white  or  faintly  pinkish  petal-like  bracts  an  inch  or  two  in 
length.  These,  unlike  those  of  the  eastern  flowering  dogwood,  are 
pointed  and  not  indented  at  their  tips.  The  berries  are  a  shiny 
red  and  much  like  those  of  its  eastern  brother.  The  wood  is 
lighter  and  less  dense,  and  but  little  used. 


THE   DOGWOOD   AND    GUM  241 

The  western  dogwood  is  similarly  an  under  tree,  frequently  of 
Douglas  fir,  redwood,  or  western  hemlock,  and  reaches  its  largest 
size  in  the  Douglas  fir  forests  of  the  Puget  Sound  country,  where  it 
may  reach  a  height  of  100  feet  and  a  diameter  of  2  feet,  but  is  usually 
from  40  to  60  feet  tall  and  with  a  trunk  diameter  of  from  8  to  12 
inches.  It  probably  reaches  an  age  of  from  150  to  250  years,  is  a 
vigorous  annual  seeder  of  persistent  vitality,  and  is  found  from 
southern  British  Columbia  near  the  coast,  that  is,  the  lower  Fraser 
River  and  Vancouver  Island  region,  through  Washington,  Oregon 
and  Cahfomia  to  the  San  Jacinto  Mountains  and  the  western 
slopes  of  the  Sierra  Nevadas. 

The  dogwoods  all  have  rather  characteristically  shaped  and 
veined  leaves,  and  consequently  considerable  is  known  of  their 
geological  history.  Over  50  fossil  forms  have  been  described,  and 
the  oldest  kno\vn  of  these  come  from  the  Upper  Cretaceous.  A 
dozen  different  forms  have  been  recorded  from  the  rocks  of  that 
far  off  age,  and  the  oldest  of  these  occurrec^  in  western  Greenland 
and  in  beds  of  approximately  the  same  age  along  the  Atlantic  coast 
of  North  America  of  that  time,  when  the  coast  was  somewhat 
west  of  where  it  is  today.  Similar  ancient  dogwoods  left  their 
leaves  in  the  initial  sandy  deposits  that  were  laid  down  by  the 
Upper  Cretaceous  sea  that  swept  over  our  western  plains  country 
from  the  Gulf  of  Mexico. 

Dogwood  leaves  continue  to  turn  up  throughout  the  Cretaceous 
in  Colorado,  Wyoming,  Montana,  Vancouver  Island  and  Green- 
land, but  none  have  thus  far  been  found  outside  of  North  America 
except  for  a  single  form  recorded  from  supposed  Upper  Cretaceous 
deposits  in  Spitzbergen.  These  facts  suggest  that  America  was 
near  the  place  of  origin  of  the  dogwood  tribe.  At  least  dogwoods  do 
not  seem  to  have  reached  Europe  until  much  later.  What  happened 
in  Asia  in  those  far  off  days  can  only  be  surmised,  since  we  know 
scarcely  anything  of  the  later  floral  history  of  that  vast  area. 

During  the  first  stage  of  the  succeeding  Tertiary  period — the 
Eocene,  or  dawn  period  of  modern  life — ^13  species  of  the  dogwood 
have  been  discovered.  The  bulk  of  these  are  American,  but  there 
was  a  single  form  in  France  and  2  others  are  known  from  the  late 


242  TREE    ANCESTORS 

Eocene  of  Sachalin  Island  on  the  east  coast  of  Asia.  In  North 
America  the  Eocene  records  are  numerous,  and  most  abundant  in 
the  rocks  of  late  Eocene  age,  and  in  our  more  northern  States  and 
still  farther  northward. 

The  southernmost  record  is  New  Mexico,  the  others  include 
Colorado,  Wyoming,  Montana,  California,  Oregon  and  British 
Columbia.  Eocene  dogwoods  are  found  in  Greenland  and  Spitz- 
bergen.  One  described  from  Wyoming  is  based  upon  a  characteris- 
tic fossilized  flower  head  with  the  enlarged  bracts  much  like  our 
existing  flowering  dog\vood. 

The  Oligocene  records  of  the  dogwood  drop  to  3  species  described 
from  Italy,  Prussia  and  Bohemia.  This  scanty  record  for  those 
times  is  due  partly  to  adverse  conditions  and  partly  to  the  carcitys 
of  plant  records  of  that  age,  particularly  in  North  America.  The 
record  becomes  more  representative  in  the  succeeding  Miocene 
times  for  some  20  species  of  dogwood  have  been  described  from 
deposits  of  that  age.  These  are  mostly  European  and  Miocene 
species  which  were  widely  scattered  over  Europe  at  that  time  from 
France  to  Austria  and  Hungary.  In  this  country  1  form  has  been 
found  in  deposits  supposed  to  be  of  Miocene  age  in  the  Yellowstone 
Park,  and  2  others  have  been  recorded  from  California. 

In  succeeding  Pliocene  times  which  brought  the  Tertiary  period 
to  a  close  the  variety  and  abundance  of  dogwoods  appears  to  have 
waned.  I  say  appear,  since  the  Pliocene  records  are  so  incomplete 
that  the  merely  negative  evidence  may  be  of  no  value.  Four 
different  dogwoods  are  reported  from  PHocene  deposits  and  all  of 
these  are  from  Old  World  locaHties.  This  does  not  mean  that  the 
dogwood  became  extinct  in  North  America  during  the  PHocene  and 
reappeared  in  modern  times — the  mere  fact  that  they  could  not 
have  attained  their  present  day  distribution  under  existing  climatic 
conditions  is  sufficient  proof  that  this  was  not  the  case,  but  that 
our  American  PHocene  plant  record  is  very  incomplete. 

The  Old  World  PHocene  forms  have  been  found  in  France,  Spain 
and  Italy  in  Europe,  and  in  Japan.  The  dogwood  was  thus  a 
member  of  the  forest  flora  that  at  that  time  extended  almost  un- 
brokcnly  from  Portugal  eastward  to  Japan.     Traces  of  this  forest 


THE   DOGWOOD   AND    GUM  243 

flora  have  been  discovered  at  various  scattered  localities  throughout 
that  vast  area,  as  have  also  the  remains  of  a  considerable  repre- 
sentation of  the  terrestrial  animal  life  commonly  known  as  the 
Hipparion  fauna  from  the  abundance  of  the  remains  of  extinct 
horses  of  that  genus  that  have  been  found  in  it. 

The  Pleistocene  or  glacial  period,  which  fills  the  interval  in 
geological  history  between  the  Tertiary  and  the  present  has  yielded 
the  remains  of  dogwoods  of  2  existing  species  in  Europe,  namely, 
Cornus  sanguinea  in  England  and  Germany,  and  Cornus  mas  in 
Holland  and  Hungary,  A  single  seed  of  an  undetermined  species 
of  dogwood  has  been  found  in  the  Pleistocene  deposits  of  New  Jer- 
sey, and  recently  a  second  species  based  upon  the  seeds  has  been 
reported  from  a  deposit  of  this  age  in  the  city  of  Washington. 
Doubtless  a  comprehensive  study  of  American  Pleistocene  plant 
beds,  which  has  never  been  made,  would  add  much  to  the  last 
stages  of  dogwood  history. 

THE   GUMS 

The  various  trees  embraced  under  this  name  are  better  known 
to  the  professional  botanist  and  lumberman  than  they  are  to  the 
layman.  They  comprise  the  tupelo,  cotton,  and  sour  gum,  and 
are  not  related  to  the  sweet  gum,  Liquidambar,  whose  history  has 
been  sketched  in  an  earlier  chapter.  The  gums  are  referred  to  a 
genus  known  as  Nyssa,  the  name  of  a  water  nymph,  in  allusion  to 
the  fact  that  most  of  the  gums  grow  in  wet  soils,  and  one  in  partic- 
ular is  found  in  standing  water  in  the  sloughs  or  swamps  of 
our  southern  States,  in  which  situation  it  swells  out  its  butt  just 
like  that  of  the  bald  cypress. 

There  are  6  or  7  existing  species  of  gum,  all  of  which  are  confined 
to  southeastern  North  America  except  a  single  form  which  is  found 
in  southeastern  Asia  from  the  eastern  Himalayas  to  the  island  of 
Java,  thus  furnishing  another  link  in  the  chain  of  evidence  that 
shows  that  these  two  regions  are  vast  plant  preserves  where  the 
glaciation  of  the  Pleistocene  was  unable  to  destroy  the  Tertiary 
forest  population  that  so  largely  perished  in  all  other  parts  of  the 
Northern  Hemisphere  at  that  time. 


244  TREE   ANCESTORS 

The  gums  all  yield  a  tough  wood  which  has  an  intricately  con- 
torted and  twisted  grain,  and  are  hence  not  extensively  utilized  by 
man  because  of  this  difficulty  of  working  it.  The  gum  fruits  are 
stone  fruits  with  a  thin  oily  acidulous  flesh  which  is  utilized  and 
distributed  by  birds,  and  by  mammals  other  than  man.  In  the 
fall  of  the  year  such  bears  as  are  left  in  our  southern  States  invade 
the  somewhat  drier  swamps  of  this  season  in  search  of  gum  fruits. 
The  stones  are  rather  characteristic  being  bony  and  compressed, 
with  longitudinal  wings  or  ridges,  and  they  have  frequently  been 
found  fossil. 

A  large  number  of  fossil  forms  of  gums  have  been  described. 
Leaves  that  are  apparently  those  of  extinct  species  have  been 
found  in  Upper  Cretaceous  deposits  in  Wyoming,  Nebraska,  Kan- 
sas, and  Alabama.  During  the  early  Tertiary  gums  are  extraor- 
dinarily abundant  with  many  different  species.  From  the  iso- 
lated and  restricted  Hgnite  deposit  at  Brandon,  Vermont,  which 
has  been  mined  sporadically  when  coal  was  scarce  or  prohibitive 
in  price  in  that  region,  18  different  kinds  of  stones  of  gum  fruits 
have  been  described. 

It  is  worthy  of  comment  that  all  of  the  Upper  Cretaceous  and 
Eocene  gums  are  North  American  or  Arctic,  none  being  known 
from  the  numerous  plant  beds  of  Europe  until  OHgocene  times. 
Besides  the  abundance  of  Eocene  gum  stones  in  New  England, 
which  we  infer  from  their  abundance  in  the  tiny  lignite  deposit  in 
Vermont,  Eocene  gums  have  been  recorded  from  Montana,  Wyom- 
ing, Colorado,  New  Mexico,  Tennessee,  Louisiana  and  Texas.  In 
the  far  north  they  occurred  at  that  time  in  Alaska,  Greenland  and 
Spitzbergen. 

There  are  8  known  Oligocene  forms  of  gum.  The  scene,  in  so 
far  as  the  actual  geological  record  is  preserved  had  now  shifted  from 
the  New  to  the  Old  World,  but  this  is  due  entirely  to  the  absence 
of  Oligocene  records  in  North  America,  and  probably  not  at  all  to 
the  absence  of  gums  in  the  North  American  forests  of  those  times, 
especially  in  eastern  North  America,  although  it  is  quite  probable 
that  by  Oligocene  time  they  may  have  become  extinct  or  extremely 
hmited  by  the  dr}'ing  of  the  climate  brought  about  by  the  eleva- 


THE   DOGWOOD    AND    GUM 


245 


tion  of  the  western  mountain  ranges  which  cut  off  the  moisture 
bearing  winds  from  the  Pacific. 

Gum  stones  are  ahnost  as  common  in  the  brown  coals  of  central 
Europe  as  in  the  Brandon  lignites  of  an  earlier  day  and  the  Oligo- 
cene  records  are  principally  those  of  southern  England  and  Germany, 
showing  for  how  many  thousands  of  years  the  gums  have  been 
accustomed  to  a  swampy  habitat. 


Fig.  44.  Sketch  IMap  Showing  Present  Distribution  (enclosed   areas) 
AND  Fossil  Occurrences  of  the  Tupelo 


The  gums  appear  to  wane  in  the  later  Tertiary,  if  their  geological 
record  as  it  is  now  kno^\Tl  may  be  taken  as  a  safe  guide.  Thus 
there  are  but  4  or  5  Miocene  species.  On  the  other  hand  these 
are  widely  distributed.  An  American  Miocene  form,  again  based 
on  the  fruit  stones,  is  found  in  the  coastal  deposits  of  diatomaceous 
sediments  in  Virginia.  In  Europe  the  Miocene  records  include 
various  localities  in  Germany  and  in  the  components  of  the  now 


246  TREE    ANCESTORS 

disrupted  Austro-Hungarian  empire  (Styria,  Carinthia,  and  Croa- 
tia). One  of  the  gums  found  in  the  latter  region  is  also  recorded 
from  Siberia. 

The  Miocene  witnessed  the  last  known  gums  in  Europe,  their 
extinction  on  that  continent  having  apparently  been  due  to  cli- 
matic changes  long  anterior  to  the  glacial  period  for  none  are  known 
from  European  Pleistocene  deposits  which  is  a  reasonable  guerdon 
of  their  absence  at  that  time  for  many  of  these  Pliocene  plant  beds 
were  swamp  deposits.  The  known  Pliocene  or  late  Tertiary  gums, 
3  in  number,  are  all  North  American,  and  very  much  like  some  of 
our  existing  American  species,  of  which  they  were  undoubtedly 
the  ancestors.  They  come  from  New  Jersey  and  southern  Alabama. 
The  Pleistocene  gums  are  likewise  North  American  and  represent 
still  existing  species.  They  are  known  from  New  Jersey,  Maryland, 
Virginia,  North  CaroHna,  Alabama,  and  Kentucky. 


CHAPTER  XXIV 

Sassafras,  Spice-bush  and  Bay 

The  sassafras,  spice-bush  and  bay  belong  to  a  family,  the  Laura- 
ceae,  that  is  mainly  tropical  in  its  modern  distribution  and  which 
contains  over  1000  species  many  of  which  are  valuable  timber  trees 
in  the  tropics  or  yield  camphor,  cinnamon,  alligator  pears,  and 
other  less  well  known  articles  of  commerce.  Very  few  members 
of  the  family  are  found  in  the  Temperate  Zone  and  it  is  especially 
well  represented  at  the  present  time  in  northern  South  America. 

THE  sassafras 

None  of  our  native  trees  surpass  the  sassafras  in  the  personal 
interest  that  it  arouses.  Many  of  my  readers  are  familiar  with  it 
and  have  noticed  the  sometimes  mitten-Hke  shape  of  some  of  its 
leaves,  or  know  the  fragrant  root,  but  most  of  them  I  suspect  think 
of  the  sassfras  as  a  bush  or  small  tree,  and  yet  it  frequently  reaches 
a  height  of  125  feet  and  occasionally  a  trunk  diameter  of  7  feet. 
The  sassafras  is  not  uncommon  in  southern  New  England,  and  I 
have  a  tree  on  my  place  in  eastern  Connecticut  some  90  feet  tall 
and  with  a  trunk  a  foot  in  diameter.  This  tree  always  calls  up 
memories  of  the  tropics  for  the  dark  green  leaves  are  massed  toward 
the  ends  of  the  branches  in  a  way  characteristic  of  many  of  its 
tropical  relatives,  and  its  whole  appearance  seems  exotic,  and  sug- 
gestive of  the  Spanish  Main  rather  than  staid  old  New  England. 
In  lieu  of  gold  or  precious  stones  Captain  John  Smith  sent  the  first 
ship  back  to  old  England  loaded  with  sassafras,  and  this  was,  so 
far  as  I  know  the  first  and  last  incursion  of  the  sassafras  in  any 
large  way  into  the  commerce  of  the  world,  although  the  Choctaw 
Indians  are  said  to  make  a  soup  flavor  from  its  leaves,  and  the 
aromatic  principle,  especially  of  the  roots,  furnishes  a  mild  aromatic 
stimulant,  and  yields  upon  distillation  oil  of  sassafras,  sparingly 
used  in  perfumery  and  soapmaking. 

247 


248 


TREE   ANCESTORS 


Until  a  few  years  ago  when  two  species  were  recognized  in 
central  China  sassafras  was  known  as  a  monotypic  genus,  that  is 
to  say,  one  \\dth  only  single  hving  species — for  botanists,  like  most 
other  people,  have  rarely  paid  any  attention  to  other  than  living 
species. 

The  great  systematist  Linnaeus  called  the  sassafras  Laiirus 
sassafras  in  allusion  to  a  name  of  Spanish  origin  in  Florida,  and 
when  the  old  and  composite  genus  Laurus  was  dismembered,  its 
scientific  name  became  Sassafras  sassafras  which  is  in  conformity 


Fig.  45.  Sketch  ]SIap  Showing  Present  Distribution  (solid  black)  and 
Fossil  Occurrences  (circles)  of  the  Sassafras 


with  the  rules  which  modem  systematic  botanists  observe,  although 
Nees  who  in  1831  established  the  genus  Sassafras  for  its  reception 
called  our  American  tree  Sassafras  officinale  in  allusion  to  its  place, 
if  but  a  minor  one,  in  the  pharmacopeia. 

The  wood  is  soft,  brittle  and  weak,  but  durable  like  that  of  most 
members  of  this  large  family.  It  is  sometimes  used  for  posts  and 
rails  where  the  tree  is  abundant,  and  some  of  its  tropical  relatives 
3deld  a  very  hard  wood  that  is  almost  indestructible. 


SASSAFRAS,    SPICE-BUSH    AND    BAY  249 

Our  American  sassafras  ranges  from  Massachusetts  westward 
to  Iowa  and  Kansas  and  from  Ontario  and  Michigan  southward  to 
Florida  and  Texas.  Just  why  it,  along  with  the  two  Chinese  species 
should  have  remained  a  Temperate  Zone  type  in  contrast  to  the 
vast  majority  of  its  relatives  is  a  mystery.  To  be  sure  its  most 
ancient  home  was  outside  the  Equatorial  Zone,  but  this  was  also 
true,  at  least  ancestrally,  of  many  of  its  kin. 

The  ancestry  of  the  sassafras  has  this  remarkable  feature— that 
the  most  ancient  known  forms  are  quite  like  some  of  those  stiU 
existing  as  regards  their  leaves,  showing  both  the  two  lobed  mitten- 
like and  the  three  lobed  leaves  with  which  we  are  familiar,  but 
apparently  without  entire  leaves.  They  are  also  remarkable  in 
that  they  are  found  in  somewhat  older  rocks  than  most  of  the  flower- 
ing plants.  Toward  the  close  of  Lower  Cretaceous  time,  in  the  last 
or  Albian  stage,  as  geologists  call  it,  of  that  period,  several  different 
kinds  of  sassafras  have  been  found.  One  of  these  comes  from  west- 
em  Europe  (Portugal)  and  three  from  eastern  North  America 
(Maryland  and  Virginia). 

It  seems  incredible  that  in  those  far  off  days  of  the  age  of  dino- 
saurs trees  so  Hke  their  modern  descendants  should  already  have 
been  in  existence.  That  they  occur  on  both  shores  of  the  Atlantic 
indicates  a  still  more  ancient  ancestry,  and  an  origin  in  a  third 
region  accessible  to  both  Portugal  and  Maryland.  That  this  was 
toward  the  north  rather  than  in  Asia  seems  probable  from  the  rec- 
ords of  Upper  Cretaceous  time,  of  not  only  the  sassafras,  but  of 
many  other  plant  types. 

Leaves  like  those  of  the  sassafras  are  often  exceedingly  abundant 
and  varied  in  certain  rocks  of  Upper  Cretaceous  age.  Over  a 
dozen  species  have  been  described,  and  their  leaves  are  especially 
abundant  in  the  shore  deposits  of  the  Upper  Cretaceous  sea  that 
advanced  over  our  western  great  plains  country  (the  Dakota  sand- 
stone), and  in  the  muds  of  the  estuaries  and  lagoons  that  skirted 
the  corresponding  sea  along  our  east  coast  at  the  time  it  commenced 
to  encroach  on  the  old  land. 

At  least  3  different  kinds  of  sassafras  were  present  at  that  time 
in  western   Greenland    and   along  our  eastern    coast  from    New 


250 


TREE   ANCESTORS 


SASSAFRAS,    SPICE-BUSH    AND    BAY  251 

York  to  Alabama.  In  Europe  they  are  known  from  Bohemia  and 
Mora\ia,  and  they  have  been  even  recorded,  but  on  somewhat 
doubtful  authority,  from  Argentina.  At  no  later  time  are  they  as 
varied  as  during  the  Upper  Cretaceous. 

During  the  Eocene  4  or  5  different  forms  of  sassafras  are  knoAMi 
from  widely  scattered  localities  which  include  France,  Germany, 
Greenland  and  British  Columbia.  In  succeeding  Oligocene  time 
but  2  species  are  known  and  these  are  both  from  European  localities, 
in  fact  the  only  items  of  record  in  the  later  geological  history  of  the 
sassafras  come  from  the  records  in  the  European  rocks.  As  I 
have  explained  in  connection  with  several  other  of  our  trees,  this 
is  largely  due  to  the  paucity  of  later  Tertiary  plant  records  in 
North  America,  especially  in  those  regions  where  the  sassafras 
existed  during  those  times. 

The  Miocene  records  are  of  6  or  7  species  found  in  Spain,  France. 
Italy,  Baden,  Styria  and  Bohemia.  During  the  succeeding  Plio- 
cene times  one  of  the  Miocene  species  sur\ived  in  Europe,  and  I 
have  pictured  several  leaves  of  this  form  in  order  to  emphasize  how 
like  the  modern  sassafras  leaves  they  were,  and  the  further  fact 
of  the  many  modern  North  American  and  Asian  types  that  lived 
in  Europe  during  the  Pliocene  and  until  the  coming  of  the  Pleisto- 
cene glaciers.  In  fact  a  sassafras  leaf  has  been  found  in  France 
as  late  as  the  deposits  of  the  third  Interglacial  stage  of  the  Pleisto- 
cene, showing  that  it  survived  three  Glacial  periods  on  that  con- 
tinent and  only  succumbed  filially  during  the  fourth  or  final  glacia- 
tion  that  came  to  a  close  only  a  few  thousand  years  ago  and  after 
the  men  of  the  Old  Stone  Age  had  already  been  a  long  time  in 
western  Europe. 

THE    SPICE-BUSH 

The  spice-bush,  or  benjamin-bush  as  it  is  sometimes  called  should 
be  familiar  to  all  those  who  tramp  the  spring  woods.  Its  clusters 
of  fragrant  bright  yellow  flowers  borne  close  to  the  stems  as  in  so 
many  tropical  trees  and  shrubs  makes  it  a  conspicuous  object  in 
the  bare  woods  of  early  spring  for  it  blooms  long  before  its  leaves 
come  out,  as  early  as  March  in  our  northern  States  and  still  earlier 


252  TREE    .VNCESTORS 

in  the  South.  In  1922  I  noticed  it  in  blossom  in  Mar^-land  in 
February  and  in  1923  it  was  out  in  January.  We  have  2  species 
in  eastern  North  America — a  more  northern  and  a  more  southern 
one,  their  combined  range  being  almost  identical  with  that  of  the 
sassafras,  and  overlapping  one  another  in  the  Carolinas.  Techni- 
cally they  are  referred  to  the  genus  Benzoin  named  because  the 
fragrance  of  the  spice-bush  suggests  that  of  benzoin  gum.  Both 
are  species  that  frequent  moist  places  in  low  w^oods  or  along 
streams.  In  some  localities  they  go  by  the  name  of  fever-bush  or 
^vild  all-spice,  the  latter  an  appropriate  name  for  the  aromatic  spicy 
odor  of  the  blossoms,  bark  or  crushed  leaves.  Later  in  the  year  when 
the  ovate  leaves  have  unfurled  and  before  the  small  red  plum-like 
fruits  have  ripened  some  search  is  required  to  recognize  the  spice- 
bush  even  in  its  favorite  haunts. 

In  addition  to  our  2  eastern  American  forms  which  never  reach 
proportions  larger  than  bushes,  there  are  4  or  5  species  of  south- 
eastern Asia  which  are  trees  and  have  trilobate,  sassafras-like 
leaves,  so  that  the  spice-bush,  like  so  many  other  of  the  t>pcs  we 
have  been  considering,  illustrates  a  past  general  distribution  and 
a  post-Pleistocene  restriction  to  the  southeastern  parts  of  Asia  and 
North  America,  paralleling  in  its  history  that  of  the  sassafras, 
but  much  less  fully  known  in  the  case  of  the  former. 

Eight  different  fossil  species  have  been  described  and  all  of  these 
are  more  like  the  existing  Asiatic  than  they  are  like  the  existing 
American  forms.  The  oldest  known  are  2  varieties  found  in 
the  Upper  Cretaceous  of  Kansas  and  Texas,  contemporaneous  w'ith 
several  of  the  sassafras  forms  of  that  time.  There  is  an  early 
Eocene  form  in  France  and  a  late  Eocene  form  in  western  Green- 
land. Three  Oligocene  species  are  recorded  from  P>ance,  Italy 
and  Gemiany. 

In  succeeding  ^Miocene  times,  especially  in  the  later  days  of  the 
Miocene,  4  different  species  of  Benzoin  ha\'e  been  discovered. 
These  are  found  in  Spain,  France,  Switzerland,  Italy,  Baden, 
Prussia,  Silesia  and  Croatia.  Three  of  these  lived  on  in  Europe  and 
left  their  fossil  remains  in  the  Pliocene  of  Spain  and  Italy.  The 
Pleistocene  glaciation,  however,  put  an  end  to  their  long  contin- 


SASSAFRAS,    SPICE-BUSH    AND    BAY  253 

ued  European  residence,  and  apparently  blotted  them  out  in  the 
whole  region  from  Spain  to  China  where  formerly  they  presumably 
flourished  in  appropriate  situations,  leaving  them  only  in  eastern 
Asia  and  southeastern  North  America. 

THE    BAY 

The  term  bay  is  in  different  regions  the  popular  name  of  several 
different  kinds  of  swamp  plants.  As  used  here  it  applies  to  the  3 
forms  of  our  southern  States  known  as  the  red  bay,  swamp  bay 
or  Isabella-wood.  They  will  be  unfamiliar  to  most  of  my  readers, 
and  are  introduced  in  order  to  give  a  glimpse  into  the  history  of  a 
member  of  this  great  family  of  the  Lauraceae  which  is  essentially 
tropical  rather  than  temperate  in  its  modern  development,  although 
our  bays  range  northward  as  far  as  southern  Maryland.  They  are 
either  trees  or  shrubs,  those  of  the  tropics  being  mostly  trees,  our 
boys  being  either,  with  ovate  or  lanceolate  leathery  leaves,  small 
not  especially  conspicuous  flowers,  and  globose  berry-like  fruits. 
Our  American  forms  are  dwellers  in  swamps  and  low  stream  bot- 
toms where  the  climate  does  not  fluctuate  as  in  other  situations 
but  this  habitat  does  not  hold  for  the  other  members  of  the  genus. 

They  are  referred  to  a  genus  called  Persea,  which  was  the  ancient 
name  of  some  now  unknown  Oriental  tree,  although  the  existing 
Perseas  are  all  Occidental  except  for  a  single  survivor  from  bygone 
days  that  at  present  inhabits  the  Canary  Islands.  There  are 
about  50  existing  species  of  Persea,  mostly  trees  of  tropical  America, 
some  of  which  furnish  the  alligator  pears  or  avocados  that  are 
now  cultivated  in  many  tropical  countries.  I  have  had  but  slight 
experience  with  the  alHgator  pears  usually  to  be  seen  on  sale  in 
our  better  fruit  stores,  but  I  can  testify  to  the  extreme  daintiness 
and  appetizing  taste  that  they  have  when  personally  collected  and 
properly  seasoned  with  sugar  and  lime-juice. 

The  geological  history  of  Persea  is  of  interest  since  it  is  somewhat 
different  from  that  of  most  of  the  trees  discussed  in  this  volume. 
The  known  fossil  species  are  about  as  numerous  as  the  still  exist- 
ing species,  that  is,  about  50  different  forms  are  known  from  the 
rocks.     Six  of  these  are  recorded  from  the  Upper  Cretaceous  in 


254  TREE    ANCESTORS 

Kansas,  Vancouver  Island,  Marthas  Vineyard,  Long  Island,  Ala- 
bama, and  Moravia. 

We  have  records  of  9  forms  during  the  Eocene.  Four  of  these 
are  from  the  early  Eocene  of  France,  1  comes  from  the  Upper 
Eocene  of  Germany,  1  from  the  Upper  Eocene  of  British  Columbia, 
and  3  from  the  early  Eocene  of  the  United  States.  One  of  the  last 
comes  from  Colorado  and  the  other  2  were  members  of  the  warm 
flora  that  spread  northward  from  equatorial  America  during  that 
period  of  mild  chmate  that  characterized  the  later  Eocene  and 
which  contained  so  many  representatives  of  this  family,  including 
even  the  cinnamon  and  camphor  trees  which  in  existing  floras  are 
confined  to  the  Old  World. 

The  Oligocene  forms  of  Persea  are  6  in  number  and  come  from 
Italy  and  southern  Germany.  Succeeding  Miocene  rocks  furnish 
many  records,  and  include  no  less  than  27  different  species.  They 
are  knowii  at  that  time  from  four  different  continental  areas  and 
occur  in  Indo-China,  southern  Chile,  Peru,  Colombia,  Italy,  Baden, 
France,  Switzerland,  Germany,  Bohemia,  Styria,  Carniola,  Croa- 
tia, Carinthia,  Transylvania,  Greece,  New  Jersey,  Colorado,  Yel- 
lowstone Park  and  California.  As  regards  the  general  facies  of 
the  flora  that  of  Pliocene  time  is  essentially  a  continuation  of  that 
of  the  later  Miocene  without  great  change. 

Eleven  different  forms  of  Persea  have  been  discovered  in  PHo- 
cene  deposits  and  these  PHocene  records  include  Spain,  France, 
Italy,  Asia  Minor  and  Brazil.  The  still  existing  species  which  I 
have  mentioned  as  surviving  in  the  Canary  Islands  is  found  in  beds 
of  Pliocene  age  in  France  and  Italy  and  in  the  volcanic  beds  of  that 
age  on  the  Lipari  Islands.  The  Pleistocene  records  are  confined  to 
the  presence  of  one  of  the  living  American  forms  which  has  been 
found  in  the  deposits  of  that  age  in  North  Carolina  and  Alabama, 
and  possibly  a  third  occurrence  in  western  Tennessee. 


CHAPTER  XXV 

The   Persimmon 

The  ebony  family  or  Ebenaceae  of  the  order  Ebenales  is  com- 
paratively large,  with  upwards  of  300  different  species  distributed 
among  5  or  6  genera,  more  than  half  of  them  being  referable  to 
the  genus  Diospyros  to  which  our  common  eastern  form  belongs. 
The  name  Diospyros  is  derived  from  the  Greek  and  means  God  or 
life-giving  or  heavenly.  Its  selection  for  these  particular  plants 
required  the  same  type  of  imagination  which  gave  to  our  common 
clams  the  name  Venus,  and  which  saw  the  mythical  shapes  embodied 
in  the  constellations.  Most  of  my  readers  are  famihar  with  our 
common  American  persimmon  or  "Possom  wood"  and  not  a  few 
will  recall  the  extremely  astringent  taste  of  its  unripe  fruits.  Many 
are  also  familiar  with  large  edible  persimmons  of  China  and  Japan 
which  are  now  often  cultivated  in  our  extreme  southern  States. 
Persimmon  wood  is  hard  and  strong  and  is  used  to  a  considerable 
extent  in  the  manufacture  of  bobbins  and  similar  articles.  This 
quahty  of  hardness  and  fineness  of  grain  runs  through  the  whole 
family  and  the  bulk  of  the  ebony  of  commerce  is  derived  from 
various  species  of  Diospyros.  According  to  the  writer  of  the  Book 
of  Ezekiel,  ebony  was  one  of  the  articles  of  merchandise  of  the 
Phoenicians  and  the  ancients  esteemed  it  even  more  than  we  do  at 
the  present  time.  Virgil  and  Pliny  mention  it  as  a  product  of 
India  and  Herodotus  relates  that  it  was  one  of  the  articles  of  tribute 
in  the  days  of  the  Persian  Empire.  Naturally  a  wood  which  has 
been  utilized  for  so  long,  a  wood  so  fine-grained,  hard,  and  heavy, 
and  susceptible  of  such  a  high  polish  was  thought  to  possess  many 
mystic  virtues.  It  was  used  for  making  scepters,  images  and  drink- 
ing cups  because  of  its  supposed  antagonism  to  poison.  Pau- 
sanius  relates  that  the  ebony  tree  produced  neither  leaves  or  fruit, 
nor  was  ever  seen  exposed  to  the  sun. 

255 


256  TREE    ANCESTORS 

The  species  of  Diospyros  and  indeed  the  entire  family  to  which 
it  belongs  are,  for  the  most  part,  confined  to  tropical  and  subtropi- 
cal countries.  The  different  species  of  persimmon  or  ebony  are 
widely  distributed  and  indigenous  to  all  of  the  continents.  At 
first  sight,  it  seems  singular  that  a  tree  whose  near  relatives  are  all 
tropical  should  be  found  ranging  from  Florida  and  Texas,  north- 
ward to  southern  New  England  and  to  Iowa  and  Kansas  in  the 
west.  It  is  clear  that  present  climatic  conditions  altogether  fail 
to  explain  such  a  range.  Nor  is  it  to  be  accounted  for  by  the  sup- 
position that  the  persimmon  has  extended  its  range  northward 
from  the  tropics  during  the  few  thousands  of  years  which  have 
intervened  since  the  last  glacial  epoch.  Like  so  many  of  our  other 
American  trees,  the  real  explanation  is  to  be  sought  in  the  records 
which  are  far  older  than  those  of  post-glacial  times.  Fortunately 
the  persimmon  has  left  many  such  records  of  its  former  distribution 
extending  back  some  millions  of  years  previous  to  the  advent  of 
man  on  this  earth. 

Our  common  persimmon,  scientifically  known  as  Diospyros 
virginiana,  makes  a  rather  handsome  shade  tree  with  its  large  ovate 
glossy  leaves,  and  can  be  purchased  from  a  number  of  dealers.  Its 
fruits  were  probably  the  first  native  fruits  to  be  described,  DeSoto 
publishing  a  laudatory  account  of  them  in  1557  in  Portuguese, 
de  Laet  in  his  work  on  Virginia,  published  in  1558,  describes  the 
persimmon  in  that  State.  In  Captain  John  Smith's  narrative  of 
the  resources  of  the  New  World  there  is  to  be  found  a  long  dis- 
cussion of  the  persimmon,  and  he  says  most  aptly  of  the  fruit: 
"If  it  be  not  ripe,  it  \\dll  draw  a  man's  mouth  awrie  wdth  much 
torment." 

The  tannic  acid  in  the  immature  fruits  and  in  some  apparently 
mature  fruits  renders  them  very  astringent  with  the  result  that 
their  food  value  has  been  little  recognized.  It  is  a  common  say- 
ing that  persimmons  are  not  fit  to  eat  until  after  frost,  although 
freezing  no  more  improves  persimmons  than  it  does  other  fruits. 
The  real  truth  seems  to  be  that  the  species  includes  many  diverse 
strains,  some  with  greater  and  some  with  lesser  amounts  of  tannin, 
some  ripening  early  and  others  not  maturing  until  after  the  first 


THE   PERSIMMON  257 

frosts.  Undoubtedly  if  some  attention  was  given  to  the  selection 
•of  the  right  varieties,  to  care  of  the  trees,  pruning  and  grafting  of 
the  finer  sorts,  a  profitable  industry  could  be  built  up,  as  there  is 
no  pleasanter  fruit  than  some  persimmons,  and  none  except  the 
date  that  has  a  greater  food  value. 

We  have  a  second  species  in  the  United  States,  less  well  known 
because  of  its  more  restricted  range.  This  is  the  black  persimmon 
or  chapote,  Diospyros  texana,  found  in  the  river  valleys  from  the 
Colorado  River  of  Texas  to  the  Neuvo  Leon  in  Mexico.  It  is  a 
fair  sized,  intricately  branched  tree,  whose  fruits  of  a  black  color 
are  often  said  to  be  insipid.  They  lack  the  astringency  so  frequent 
in  our  common  persimmon,  and  I  have  found  them  fully  as  appetiz- 
ing as  the  large  Japanese  persimmons  often  grown  in  our  southern 
States. 

In  that  grand  display  of  dicotyledonous  genera  which  during 
the  mid-Cretaceous  replaced  the  old  Mesozoic  flora  of  ferns,  cy- 
cads,  and  conifers  and  which  appeared  with  such  apparent  sudden- 
ness at  a  number  of  points  in  the  Northern  Hemisphere,  we  find 
unmistakable  evidence  of  the  abundance  and  wide  distribution  of 
species  of  Diospyros.  No  less  than  17  different  forms  have  been 
described  from  the  rocks  of  this  age,  and  the  localities  where  they 
have  been  found  are  scattered  from  Australia  to  Bohemia,  Green- 
land, and  Vancouver  Island.  A  large  majority  of  these  species 
are  American,  and  they  seem  to  have  been  especially  at  home  along 
the  Cretaceous  coast  of  the  Atlantic  and  along  the  border  of  the 
Mediterranean  Sea  which  extended  northwestward  from  the  Gulf 
of  Mexico  over  much  of  our  present  Great  Plains  area.  One  of 
these  species,  well  named  Diospyros  primaeva  by  Professor  Heer 
in  1866,  is  especially  widespread  and  abundant,  being  found  not 
only  in  Iowa,  Kansas,  and  Nebraska  in  the  west  but  also  from 
Texas  eastward  through  Alabama  and  northward  in  South  Carolina, 
North  Carolina,  Maryland,  New  Jersey,  Long  Island  and  Green- 
land, or,  from  latitude  33°  to  latitude  71°  north.  That  these  early 
persimmons  were  not  very  different  from  those  of  today  is  shown 
by  their  similar  foliage,  as  may  be  seen  from  a  comparison  of  the 
leaf  of  Diospyros  primaeva  shown  in  figure  1  alongside  of  a  small 


/ 


258  TREE    ANCESTORS 

leaf  of  our  existing  Diospyros  virginiana  (fig.  3) .  Tliis  resemblance 
is  also  sho\\Ti  by  the  fossilized  remains  of  the  cahces  of  various 
species.  One  of  these  calices  from  another  early  upper  Cretaceous 
species,  recently  described  by  the  writer  is  Diospyros  vera  and  found 
in  what  is  knowm  in  the  Potomac  River  valley,  as  the  Raritan 
formation  is  also  shown  in  figure  2.  Apparently  the  habit  of 
accrescence  had  not  been  fully  formed  but  the  calyx  was  persistent 
then  as  now  and  entirely  like  a  modem  calyx  in  appearance.  It 
was  four-parted  as  it  usually  is  in  existing  persimmons  but  other 
fossil  forms  had  a  five-parted  calyx  like  a  good  many  present  day 
tropical  species.  This  feature  is  well  shown  in  a  large  fossil  calyx 
found  recently  in  the  upper  Eocene  of  southwestern  Texas  (fig.  7). 

In  the  Eocene  period,  which  succeeded  the  Cretaceous,  the  rec- 
ords of  the  fossil  occurrences  of  Diospyros,  show  that  it  was  truly 
cosmopolitan.  These  records  include  about  20  species  in  Siberia, 
Alaska  and  Greenland  on  the  north,  Canada,  various  localities  in 
Europe,  as  well  as  Colorado,  Montana,  Wyoming,  Nevada,  Oregon, 
Washington,  and  other  western  states  and  the  Canal  Zone  on  the 
South.  In  beds  of  supposed  Eocene  age  in  Panama  many  fruits 
of  a  persimmon  have  been  discovered  in  a  petrified  condition 
in  the  andesitic  tuffs.  These  fruits  are  about  the  size  of  cherries 
with  a  hard,  very  tanniferous  and  more  or  less  fibrous  flesh, 
and  8  to  10  varyingly  developed  seeds.  So  far  as  I  know  this 
is  the  only  petrified  persimmon  fruit  known.  Two  sections  of 
these  fruits  are  shown  in  figures  8  and  9.  A  leaf  of  one  of  the  early 
Eocene  forms  from  Montana  is  shown  in  figure  4.  Unfortunately, 
we  have  no  Eocene  or  later  Tertiary  records  along  the  Atlantic 
coast  of  North  America  north  of  Panama  since  the  preserved 
deposits  are  all  largely  of  marine  origin  and  contain  no  fossil 
plants.  There  is  little  doubt,  however,  that  Diospyros  continued 
to  be  an  abundant  element  in  the  arborescent  flora  of  this  area. 

The  Eocene  was  succeeded  by  the  geological  period  known  as 
the  OHgocene  in  the  rocks  of  which  age  no  fossil  plants  have  thus 
far  been  discovered  in  this  country.  In  Europe,  where  the  Oligo- 
cene  is  marked  by  a  warm  temperate  climate  and  by  shallow  lake 
and  river  deposits,  the  remains  of  Diospyros  are  very  common. 


THE   PERSIMMON 


259 


The  records  include  Greece,  Germany,  Italy,  Austria,  and  France 
and  embrace  calices  or  leaves  of  at  least  15  different  species. 
Especially  in  southern  France  where  the  climate  approached 
subtropical  conditions,  numerous  varieties  of  the  persimmon  flour- 
ished along  the  borders  of  the  shallow  gulf  which  extended  up  the 
Rhone  valley.  In  succeeding  Miocene  time,  a  period  of  luxuriant 
forests,  species  of  persimmon  are  found  throughout  Europe.  In 
America  where  the  Miocene  records  are  very  incompletely  pre- 
served,  the  persimmon   is   recorded   from   Montana,    Colorado, 


Fig.  47.  Sketch  Map  of  the  World  Showing  the  Distributional  Areas 

OF  the  Existing  Species  of  Diospyros  (solid  black)  and  the  More 

Extended  Range  of  the  Fossil  Species  (ruled   lines) 


California,  and  Oregon.  The  leaves  of  at  least  2  species  are  pre- 
served in  the  late  Miocene  upland  lake  basin  of  Florissant  in  the 
Rocky  Mountains  of  Colorado.  Specimens  of  Diospyros  calices 
from  the  Miocene  of  Switzerland  are  shown  in  figures  5  and  6. 

The  Miocene  period  was  followed  by  the  Pliocene,  a  time  during 
which  the  American  deposits  appear  to  have  been  unfavorable, 
either  because  of  their  character  or  location,  for  the  preservation 
of  fossil  plants,  since  practically  none  have  been  discovered.     In 


260  TREE    ANCESTORS 

Europe  on  the  contrary,  there  were  great  fluctuations  of  the  Medi- 
terranean Sea  which  at  one  time  covered  most  of  southeastern 
Europe  with  its  shallow  waters.  The  climate  was  consequently 
equable  and  humid  and  the  shores  were  well  wooded,  as  is  clearly 
indicated  by  the  great  abundance  of  fossil  plants  which  were  pre- 
served. The  persimmon  continued  to  be  an  abundant  element  in 
these  Pliocene  floras,  and  no  less  than  eight  dift'erent  species  of 
Diospyros  have  been  reported  from  deposits  of  this  age.  The 
locahties  include  Italy,  Spain,  France  and  Austria,  one  of  the 
French  species  being  indistinguishable  from  our  existing  Diospyros 
virginiana.  A  fortunately  preserved  Pliocene  deposit  on  the  island 
of  Java  shows  that  then  as  now,  Diospyros  was  a  prominent  ele- 
ment in  the  Malayan  flora. 

What  happened  at  the  close  of  the  Pliocene,  we  can  only  con- 
jecture, since  we  have  no  Pleistocene  records  of  Diospyros.  We 
know  that  their  range  was  gradually  restricted  through  cool  north- 
em  climates,  and  by  the  gradual  development  of  the  plains  type 
of  country  due  to  continental  growth  and  to  the  elevation  of  moun- 
tain ranges  which  shut  ofl'  the  moisture  laden  winds.  With  the 
subsequent  advance  of  the  glaciers  southward  over  Europe  in 
Pleistocene  time,  and  the  glaciation  in  the  mountains,  Pyrenees, 
Alps,  Carpathians  and  others,  which  with  the  Mediterranean  Sea 

Fig.  48.  Some  Leaves  and  Fruits  of  Extinct  Persimmons  (About  § 
Natural  Size) 

1.  Leaf  of  Diospyros  prirnacva  Heer  from  the  Upper  Cretaceous  of  New 
Jersey. 

2.  Calyx  of  Diospyros  vira  Berry  from  the  Upper  Cretaceous  of  the  District 
of  Columbia. 

3.  Leaf-print  of  a  small  leaf  on  the  existing  Diospyros  virginia>m  Linne. 

4.  Leaf  of  Diospyros  ficoidca  Lesquereaux  from  the  early  Eocene  of  Montana. 

5.  6.  Calices  of  Diospyros  brachysepala  Alex.  Braun  from  the  Miocene  of 
Switzerland. 

7.  Calyx  of  Diospyros  mirajloriana  Berry  from  the  upper  Eocene  of  Southwest 
Texas. 

8,  9.  Transverse  and  longitudinal  sections  of  the  fruit  of  Diospyros  inacdon- 
aldi  Berry  from  the  early  Tertiary  of  the  Panama  Canal  Zone. 


THE   PERSIMMON 


261 


Fig.  48 


262  TREE   ANCESTORS 

shut  off  the  retreat  of  the  numerous  Tertiary  forms,  Diospyros 
fared  but  ill  on  that  continent  and  most  of  the  species  became  ex- 
terminated. In  America  and  Asia,  a  congenial  habitat  spread 
far  to  the  southward  of  the  ice-front  and  there  were  no  dangerous 
mountain  glaciers  across  their  paths,  consequently  the  persimmons 
were  able  to  maintain  themselves  and  to  spread  northward  again 
in  the  wake  of  the  ice  sheet.  In  America,  our  common  persimmon 
forsook  temporarily  its  more  northern  haunts,  although  it  is  doubt- 
ful if  its  northern  limit  at  any  time  was  farther  south  than  the 
Potomac  River,  since  it  is  extremely  probable  that  the  extensive 
Pleistocene  glaciation  was  due  more  to  unbalanced  precipitation 
than  to  any  great  degree  of  secular  change  in  temperature. 

Much  more  might  be  written  concerning  the  geologic  history 
of  Diospyros  and  its  migrations  in  the  past,  as  well  as  something 
of  the  existing  species, — their  utility,  beauty,  and  habits  of  life, 
but  enough  has  been  recorded  here  to  show  how  immensely  remote 
its  forbears  were  and  what  an  extensive  territory  its  ancestors  once 
occupied.  In  closing,  let  me  repeat  the  cardinal  fact  first  emphasized 
in  Alfred  Russel  Wallace's  work  on  distribution,  that  the  present 
day  geographical  distribution  of  plants  is  almost  entirely  the  end 
product  of  their  distribution  in  antecedent  geological  ages  and 
that  there  is  the  most  complete  dependence  between  their  ances- 
tral history  and  the  geologic,  geographic,  and  climatic  history 
of  the  earth. 

I  have  attempted  to  summarize  the  history  of  Diospyros  in  a 
graphic  way  on  the  accompanying  small  sketch  map  of  the  world. 
The  soHd  black  indicates  the  distributional  areas  of  the  existing 
species  while  the  ruled  lines  indicate  the  larger  areas  over  which 
Diospyros  extended  its  range  during  its  geological  history.  This 
range  was  probably  more  extensive  even  than  is  indicated  since 
data  are  not  available  for  plotting  the  complete  record  which  will 
always  remain  more  or  less  incomplete. 


* 


»<»'* 

C* 


INDEX 


Abbotts  oak,  132 
Abele,  89 

Abrahams  oak,  131 
Acacia  family,  191 
Acer,  216 
Aceraceae,  216 
Agents  of  fossilization,  1 1 
Alder,  leaves  of,  113 

range  of,  113 

sketch  of,  112 
Alfreds  oak,  133 
Alligator  pears,  253 
Alnus,  112 

American  chestnut,  142 
Anacardiaceae,  206 
Ancestral  platanus  leaves,  161 
Antillean  forests,  37 
Arbol  de  la  noche  triste,  59 
Arctic  birch,  97 
Arctic  hazels,  105 
Arctic  willows  in  Europe,  86 

map  of,  87 
Ash,  geologic  history  of,  229-232 

leaves  of,  226 

range  of,  229 

sketch  of,  225 

species  of,  228 

utilization  of,  227 

wood  of,  226 
Aspen,  89 

Atavistic  leaves  of  liriodendron,  174, 
Atlantic  region,  forests  of,  30 
Avocado,  253 


Bald  cypress,  longevity  of,  59 
size  of,  58 
sketch  of,  56 
vitality  of,  57 


175 


Bartram,  Wm.,  quoted,  57 
Basswood,  honey  of,  234 

sketch  of,  233 

species  of,  254 
Eastwood,  234 
Bay,  geologic  history  of,  253,  254 

sketch  of,  253 

species  of,  254 
Bean  family,  191 
Bee  tree,  234 
Beech  family,  119,  129 
Beech,  distribution  of,  135 

illustrations  of,  125 

oldest  known,  122 

origin  of  name  of,  121 

range  of,  120 

sketch  of,  119 
Benjamin  bush,  251 
Betula,  species  of,  97 
Betulites,  101 
Big  trees,  distiibution  of,  43 

longevity  of,  45 

size  of,  43 

sketch  of,  38 

wood  of,  45 
Birch  family,  96 
Birches,  distribution  of,  99 

illustrations  of,  115 

sketch  of,  96 
Bitter  ash,  229 
Black  alder,  213 
Black  ash,  228 
Black  locust,  193 
Black  persimmon,  257 
Boscobel  oak,  132 
Box  alder,  216 
Butternut,  73 
Buttonball,  sketch  of,  157 
Buttonwood,  157 


263 


264 


INDEX 


Calcification,  11 

Cape  ash, 229 

Carya,  69 

Cari)inites,  109 

Caqiinus,  origin  of  name,  107 

Castagno  di  cento  cavalli,  140 

Castanea,  origin  of  name,  140 

Castanopsis,  129 

distribution  of,  135 
Cataclj'sms,  how  explained,  3 
Cedar  elm,  149,  153 
Celtis,  origin  of  name,  154 
Cenozoic  era,  8 
Central  American  forests,  37 
Cercis,  201 
Chapote,  257 
Charlemagnes  oak,  132 
Charter  oak,  133 
Chestnut  blight,  142 
Chestnuts,  fossils  of,  143 

range  of,  141 

size  of,  143 

sketch  of,  140 

wood  of,  143 
Chinese  hickory,  70 
Chinese  tulip  tree,  171 
Chinese  wax,  227 
Christmas  holly,  212 
Clammy  locust,  196 
Climate,  4,  6 

Coffee  beans,  fossils  of,  195 
Concord  elm,  148 
Cornel  family,  239 
Cornus,  origin  of  name,  239 
Cork  elm,  149 
Cork  oak,  136 

Corylus,  origin  of  name,  103 
Cotton  gum,  243 
Costa  Rica  region,  38 
Cretaceous,  alders  of,  114 

beeches  of,  122 

birches  of,  101 

geography  of,  17 

life  of,  48 

oaks  of,  137 


poplars  of,  90 
sequoias  of,  49 
sycamores  of,  158 
walnuts  of,  74 
willows  of,  84 
Cretaceous  period,  8 
Cypress  knees,  57 


Dahoon,  213 
Deciduous  forests,  32 
Devil  wood,  225 
Diospyros,  256 
Dipteronia,  216 
Dogwood,  flowers  of,  239 

fruit  of,  240 

geologic  history  of,  241-243 

leaves  of,  241 

range  of,  240 

sketch  of,  239 
Drimys,  165,  166 
Dryophyllum,  129 

descendants  of,  130 

illustrations  of,  142 

occurrences  of,  142 

E 

Ebony  family,  255 
Elm  family,  146 

fruits  of,  147 
Elms,  geologic  record  of,  149 

illustrations  of,  151 

in  the  Pleistocene,  153 

range  of,  147 

sketch  of,  147 
Engelhardtia,  fruit  of,  77 

range  of,  76 
Eocene,  alders  of,  110 

beeches  of,  123,  127 

birches  of,  102 

chestnuts  of,  143 

cypress  of,  61 

elms  of,  149 

geography  of,  22 

hazels  of,  105 


INDEX 


265 


Eocene — con  tin  tied 

hickories  of,  71 

hornbeams  of,  109 

oaks  of,  138 

poplars  of,  91 

sequoias  of,  52 

sycamores  of,  160 

walnuts  of,  74 

willows  of,  85 
Eocene  epoch,  8 
Evelyn,  quoted,  107,  157 
Evergreen  beeches,  121 
European  elm,  148 


Fayum,  Tertiary  climate  of,  76 

Fenneman,  N.  M.,  cited,  30 

Fever  bush,  213 

Filberts,  104 

Forests  of  Atlantic  region,  30 

of  Pacific  region,  33 
Forests  of  North  America,  28 
Forsythia,  225 
Fossil  Arctic  poplars,  91 
Fraxinus,  origin  of  name,  226 
Fringe  tree,  225 


Gall  berry,  213 

Garden  of  Gods,  how  formed,  3 

Geismar  oak,  131 

Geography  of  the  Cretaceous,  17 

Geography  of  the  Eocene,  21 

Geography  of  the  Oligocene,  24 

Geologic  time,  how  reckoned,  14 

Geological  history  of  North  America, 16 

Geological  principles,  3 

Geological  time  table,  8 

Geological  time  units,  6 

Gilpin,  quoted,  225 

Glacial  period,  5 

Glacial  stages,  25 

Gleditsia,  origin  of  name,  197 

Green  ash,  228 

Guatemalan  region,  38 


Gum,  distribution  of,  245 

geologic  history  of,  244-246 

range  of,  243 

sketch  of,  243 

wood  of,  244 
Gum,  Cotton,  243 

Red,  181 

Sour,  243 

Sweet,  181 

Tupelo,  243 
Gymnocladus,  200 

H 

Hackberries,  fossils  of,  156 

fruits,  155 

illustrations  of,  151 

in  North  America,  155 

range  of,  155 

size  of,  155 

sketch  of,  154 

species  of,  154 
Hamamelidanthium,  190 
Hamamelidoxylon,  190 
Hamamelis,  origin  of  name,  188 
Hamamelites,  189 
Harshberger,  J.  W.,  cited,  36 
Hazel,  leaves  of,  105 

range  of,  104 

sketch  of,  103 

species  of,  103 
Hickory,  in  Alaska,  71 

in  China,  70 

in  Europe,  71 

longevity  of,  72 

range  of,  70 

wood  of,  69 
Hickories,  sketch  of,  69 
Hollen,  212 
Holly,  folklore  of,  211 

fossil  species  of,  214 

geologic  history  of,  214,  215 

rangeof,  212,  213 

size  of,  212 

sketch  of,  211 
Honey  locust,  flowers  of,  198 

geologic  history  of,  199 


266 


INDEX 


Honey  locust — conlinued 

leaves  of,  198 

pods  of,  199 

size  of,  198 

sketch  of,  197 
Hop  hornbeam,  geologic  record  of,  111 

range  of,  1 11 

sketch  of,  110 
Hornbeam,  Hop,  110 
Hornbeam,  fossil  species  of,  109 

range  of,  108 

sketch  of,  107 

I 

Ice  age,  25 

Eex,  212 

lUicium,  164,  165 

Illustrations  of  ancestral  buttonballs,  161 

of  beeches,  125 

of  birches,  115 

of  coffee  beans,  195 

of  elms,  151 

of  hackberries,  151 

of  liquidambars,  187 

of  liriodendrons,  177 

of  locusts,  195 

of  maples,  219 

of  oaks,  145 

of  poplars,  93 

of  persimmons,  261 

of  red  buds,  192 

of  tulip  trees,  177 

of  walnuts,  79 

of  willows,  93 
Impressions,  12 
Inclusions,  11 
Infiltration,  11 
Ink  berry,  213 
Insect  wax,  227 
Interglacial  periods,  25 
Isabella  wood,  253 

J 

Japanese  persimmons,  257 
Jasmine,  225 
Jove's  own  tree,  131 


Judas  tree,  fossils  of,  192 

geologic  history  of,  203-205 

leaves  of,  202 

range  of,  203 

sketch  of,  201 
Juglans,  origin  of  name,  73 
Jurassic  period,  8 


Kadsura,  165 

Kentucky  cofTee  tree,  flowers  of,  200 

fossils  of,  195 

geologic  history  of,  201 

leaves  of,  200 

size  of,  200 

sketch  of,  200 

wood  of,  201 
Krameria  family,  191 


Lacquer,  207 
Lauraceae,  247 
Laurel  family,  247 
Leguminosae,  191 

species  of,  193 

utilization  of,  191 
Lilac,  225 
Lime,  234 
Linden,  age  of,  235 

geologic  history  of,  236-238 

size  of,  235 

sketch  of,  233 

species  of,  234 

utilization  of,  235 

wood  of,  233 
Linden  family,  233 

distribution  of,  233 
Linn,  234 
Liquidambar,  extinct  species  of,  184 

fossils  of,  187 

in  the  Eocene,  185 

in  the  Miocene,  186 

in  the  Oligocene,  185 

in  the  Pleistocene,  186 

in  the  Pliocene,  186 


INDEX 


267 


Liriodendron,  165,  166,  233 

origin  of  name,  171 
Locust,  flowers  of,  194 

fossils  of,  195 

geologic  history  of,  196,  197 

range  of,  193 

size  of,  193 

sketch  of,  193 

wood  of,  194 
Lombardy  poplar,  89 
Lyell,  Charles,  4 


Magnolia,  flowers  of,  167 

fossils  of,  166 

geologic  history,  169 

leaves  of,  168 

origin  of  name,  167 

range  of,  168 

sketch  of,  167 
Magnolia  family,  165 

distribution  of,  165 

map  showing  distribution,  166 

origin  of,  165 
Manna  ash,  228 
Manna  of  Scriptures,  228 
Maple  family,  216 

Map  of  Pleistocene  arctic  willows,  87 
Maples,  ashes  of,  217 

fossils  of,  219 

fruits  of,  220 
Maples,  geologic  history  of,  221-224 

leaves  of,  220 

range  of,  218 

sap  of,  218 

sketch  of,  216 

utilizationof,  217,  218 

wood  of,  217 
Maple  sugar,  218 
Mate,  213 
Mesozoic  era,  8 
Mexican  cypress,  59 
Michelia,  165 
Mimosa  family,  191 


Miocene,  alders  in,  116 

beeches  in,  127 

birches  in,  102 

chestnut  in,  143 

cypress  in,  62 

hickories  in,  71 

hornbeam  in,  109 

magnolia  in,  170 

maple  in,  222 

oaks  in,  138 

persimmons  in,  259 

platanus  in,  162 

poplars  in,  92 

sequoias  in,  52 

walnuts  in,  75 

willows  in,  85 
Miocene  epoch,  8 
Mistletoe,  131 
Mountain  ash,  229 
Muir,  John,  cited,  42 

N 

Negundo,  216,  220 
New  Jersey  in  Jurassic  time,  47 
North  America,   Cretaceous  geography 
of,  17 

Eocene  geography  of,  21 

forests  of,  28 

geologic  history  of,  16 

Oligocene  geography  of,  24 
Nothofagus,  122 

distribution  of,  135 
Nyssa,  origin  of  name,  243 


Oak  of  Mamre,  131 
Oak  of  Ophrah,  131 
Oaks,  ancestors  of,  130,  139 

association  with  mistletoe,  131 

illustrations  of,  145 

range  of,  132 

sketch  of,  129 

species  of,  133 

wood  of,  136 
Oil  of  wintergreen,  101 


268 


Oligocene,  alders  in,  116 

buttonballs  in,  162 

beeches  in,  127 

birches  in,  102 

cypress  in,  61 

hickories  in,  71 

maple  in,  221 

oaks  in,  138 

poplars  in,  91 

sequoias  in,  52 

walnuts  in,  75 

willows  in,  85 
Oligocene  epoch,  8 

geography  of,  24 
Olive  family',  225 
Oreomunnea,  range  of,  76 


Pacific  region,  forests  of,  33 
Paleozoic  era,  8 
Paper  birch,  98 
Paraguay  tea,  213 
Pasania,  129 

range  of,  142 
Pea  family,  191 
Pecan  hickory,  71 
Peh-la,  227 
Persimmon,  distribution  of,  259 

fossils  of,  261 

geologic  history  of,  257-262 

sketch  of,  255 

wood  of,  255 
Petrification,  11 
Planer  tree,  fossils  of,  154 

range  of,  153 

sketch  of,  153 

species  of,  153 
Plant  impressions,  12 
Platanus,  ancestors  of,  159 

in  Cretaceous,  158 

size  of,  158 

sketch  of,  157 
Pleistocene,  alders  in,  118 

ash  in,  232 

beeches  in,  128 

birches  in,  103 


cypress  in,  64 

gums  in,  186 

hazels  in,  107 

hornbeam  in,  110 

linden  in,  238 

map  of  cypress  in,  66 

maple  in,  223 

oaks  in,  139 

platanus  in, 163 

poplars  in,  94 

walnuts  in,  75 

willows  in,  86 
Pleistocene  epoch,  8,  25 
Pliny,  quoted,  157 
Pliocene,  alders  in,  118 

ash  in,  231 

beeches  in,  127 

birches  in,  102 

cypress  in,  63 

gums  in,  186 

hickories  in,  71 

hornbeams  in,  110 

linden  in,  237 

maple  in,  223 

oaks  in,  138 

platanus  in,  163 

poplars  in,  92 

sassafras  leaves  of,  250 

walnuts  in,  75 

willows  in,  85 
Pliocene  epoch,  8 
Poison  ash,  229 
Poison  ivy,  208 
Poison  oak,  208 
Pond  cypress,  58 
Poplars,  in  Greenland,  90 

range  of,  89 

sketch  of,  88 

species  of,  89 
Populus,  88 
Possum  wood,  255 
Preservation  of  plants,  10 
Prickly  ash,  229 
Privet,  225,  227 
Pterocarya,  range  of,  76 
Pussy  willow,  82 


INDEX 


269 


(Quaternary  period,  8,  25 
(^)uerciis,  origin  of  name,  133 


Red  bay,  253 
Red  bud,  201 

fossils  of,  192 
Records  of  sequoia  descent,  41 
Red  elm,  149 
Red  gum,  age  of,  182 

geologic  history  of,  184-188 

range  of,  183 

size  of,  182 

sketch  of,  181 

wood  of,  182 
Redwood,  distribution  of,  42 

size  of,  43 
Retrospective  prophec}',  4 
Robenhausian  culture,  95 
Robinia,  origin  of  name,  193 
Rock  elm,  149,  153 
Rock  folding,  3 
Rose  acacia,  196 
Rosewood,  191 
Rowan,  229 


Saint  Bernard,  quoted,  1 
Salix,  origin  of  name,  81 
Sassafras,  ancestry  of,  249 

distribution  of,  248 

geologic  history  of,  251 

in  China,  248 

in  Pliocene,  250 

size  of,  243 

sketch  of,  247 

wood  of,  248 
Sargent,  C.  S.,  cited,  34 
Scarlet  sumach,  207 
Schizandra,  165,  166 
Scotch  elm,  148 
Senna  family,  191 
Sequoia,  sketch  of,  39 


Sequoiah,  inventor  of   Cherokee  alpha- 
bet, 42 
Shreve,  F.,  cited,  31 
Silicification,  12 
Sour  gum,  243 
Southey,  Robt.,  quoted,  211 
Spanish  chestnut,  140 
Spice  bush,  geologic  history  of,  252 

sketch  of,  251 

species  of,  252 
Spitzbergen,  climate  of,  106 

flora  of,  106 
Staphorn  sumach,  207 
Sugarberry,  155 
Sumach,  geologic  history  of,  209-211 

juice  of,  207 

range  of,  207 

sketch  of,  206 

species  of,  206 
Sumach  familj',  206 

species  of,  206 
Swamp  baj',  253 
Sweet  gum,  age  of,  182 

geologic  history  of,  184-188 

range  of,  183 

size  of,  182 

sketch  of,  181 

wood  of,  182 
Swiss  lake  dwellings,  beech  in,  121 

walnuts  in,  73 
Sycamore,  157 
Sj'ringa,  225 


Tanbark  oak,  129 

Taulauma,  165,  166 

Tennyson,  Alfred,  quoted,  1,  112,  233 

Terramara  period,  95 

Tertiar}^  period,  8 

North  America  during,  21-25 
Thayer,  cited,  36 
Thors  tree,  103,  188 
Tiliaceae,  233 

Time,  methods  of  reckoning,  14 
Time  table  of  geology,  8 
Tortworth  chestnut,  140 


270 

Travertines,  12 
Triassic  period,  8 
Trochodendraceae,  91 
Trous.  linden  at,  2v>5 
Tulii)  tree,  ancestors  of,  173 

atavistic  leaves  of,  175 

flowers  of,  172 

fossil  leaves  of,  177 

geologic  history  of,  178,  179 

leaves  of,  1 73 

origin  of  stipules  of,  1 74 

range  of,  172 

size  of,  171 

sketch  of,  171 
Tupelo  ^uni,  243 

U 

Uniformitarianism,  4 
Unter  den  Linden,  235 
Upland  sumach,  207 


Ward,  L.  R,  cited,  160 
Water  ash,  228 
Water  elm,  153 
Water  locust,  199 
Weeping  willow,  83 
White  ash,  228 
Whitcwood,  233 
William  Wallace  oak,  133 
Willow  baskets,  82 
Willow  family,  81 
Willows,  sketch  of,  82 

sjjecics  of,  83 
Winged  elm,  153 
Witch  hazel,  blooming  of,  189 

distribution  of,  189 

geologic  history  of,  189,  190 

sketch  of,  188  ' 
\\'itch  hazel  family,  181 
Wordsworth,  Wm.,  quoted,  39 
Wych  elm,  103,  148 
\\'\-ch  hazel,  188 


\' 


Virgil,  cjuoted,  131 


W 

Wahoo,  153 
Walnut  family,  68 
Walnuts,  in  South  America, 

in  Swiss  lake  dwellings,  7. 

origin  of  name,  73 

range  of,  74 

sketch  of,  73 


Yaupon, 213 
Yellow  locust,  193 
Yellow  poplar,  171 


Zelkova,  146 
Zeus,  cradle  of. 


131 


Sans  Tache 

IN  THE  "elder  days  of  art"  each  artist  or  craftsman  enjoyed 
the  privilege  of  independent  creation.  He  carried  through  a 
process  of  manufacture  from  beginning  to  end.  The  scribe  of 
the  days  before  the  printing  press  was  such  a  craftsman.  So  was 
the  printer  in  the  days  before  the  machine  process.  He  stood  or 
fell,  as  a  craftsman,  by  the  merit  or  demerit  of  his  finished  product. 

Modern  machine  production  has  added  much  to  the  worker's 
productivity  and  to  his  material  welfare;  but  it  has  deprived  him  of 
the  old  creative  distinctiveness.  His  work  is  merged  in  the  work  of 
the  team,  and  lost  sight  of  as  something  representing  him  and  his 
personality. 

Many  hands  and  minds  contribute  to  the  manufacture  of  a  book, 
in  this  day  of  specialization.  There  are  seven  distinct  major  pro- 
cesses in  the  making  of  a  book:  The  type  must  first  be  set;  by  the 
monotype  method,  there  are  two  processes,  the  "keyboarding"  of 
the  MS  and  the  casting  of  the  type  from  the  perforated  paper  rolls 
thus  produced.  Formulas  and  other  intricate  work  must  be  hand- 
set; then  the  whole  brought  together  (''composed")  in  its  true 
order,  made  into  pages  and  forms.  The  results  must  be  checked  by 
proof  reading  at  each  stage.  Then  comes  the  "make-ready"  and 
press-run  and  finally  the  binding  into  volumes.  All  of  these  pro- 
cesses, except  that  of  binding  into  cloth  or  leather  covers,  are  carried 
on  under  our  roof. 

The  motto  of  the  Wilhams  &  Wilkins  Company  is  Sans  Tache. 
Our  ideal  is  to  publish  books  ^^ without  blemish" — ^worthy  books, 
worthily  printed,  with  worthy  typography — books  to  which  we  shall 
be  proud  to  attach  our  imprint,  made  by  craftsmen  who  are  willing 
to  accept  open  responsibility  for  their  work,  and  who  are  entitled  to 
credit  for  creditable  performance. 

The  printing  craftsman  of  today  is  quite  as  much  a  craftsman  as 
his  predecessor.     There  is  quite  as  much  discrimination  between 


poor  work  and  good.  We  arc  of  the  opinion  that  the  individuaUty 
of  the  worker  should  not  be  wholly  lost.  The  members  of  our  staff 
who  have  contributed  their  skill  of  hand  and  brain  to  this  volume  are: 

Keyboard  Composition:  IMildked  Lambert,  Harry  Susemihl, 
Sarah  Thomas. 

Casting:  Charles  Aher,  Kenneth  Brown,  Harold  Reusculing, 
Mahlon  Robinson,  George  Smith,  Ernest  Wann. 

Hand  Composition:  John  Crabill,  Harry  Harmyer,  Ray 
Kauffman,  Richard  King,  Herbert  Leitch,  Vernon  Lyons, 
George  Moss,  Henry  Murphy,  William  Nosek,  Andrew 
Rassa,  Edward  Rice,  William  Saunders. 

Proof  Reading:  Ruth  Jones,  Sarah  Katzin,  Ethel  Strasinger. 

Press  Work:  Andrew  Becker,  Paul  "  Clemmitt,  R.  S.  Galla- 
gher, Robert  Hanna.    Overlay  by  William  Harrison. 

Folding:  Lawrence  Krug. 


"n-'^m^mm 


